Life Extension Magazine®

Issue: Nov 2018

Immune Protection, Muscle Strength, Halt Plaque, And Breast Cancer

Immune Protection, Muscle Strength, Halt Plaque, And Breast Cancer

Immune protection

The immune system in the elderly: I. Specific humoral immunity.

Profound and complex changes in the immune response occur during the aging process. Immunosenescence is reflected by a sum of disregulations of the immune system and its interaction with other systems. Many of the changes would appear to implicate age-related deficiencies of the immune responses. The term immunosenescence designates therefore a sort of deterioration of the immune function which is believed to manifest itself in the increased susceptibility to cancer, autoimmune disease, and infectious disease. Evidence has been accumulating from several studies which suggest an association between immune function and individual longevity. However, there are observations, especially in very old healthy people, that several immune functions are unexpectedly well preserved and substantially comparable to those observed in young subjects. These findings raise the question of whether the alterations that can be observed in the immune parameters of the elderly are a cause or a result of underlying disease processes. Moreover, studies on centenarians revealed a remodeling of the immune system rather than a deterioration, suggesting that the changes observed during immunosenescence do not correspond to immunodeficiency. The underlying mechanisms of these events are however still unclear. The purpose of the present review is to assess the status of research on the immunobiology of aging. In this first section, we focus attention on the B cell biology of aging. In clinical practice, the changes in humoral immune responsiveness and antibody-mediated defense mechanisms could greatly influence the incidence and outcome of bacterial infections and autoimmune diseases as well as the response to vaccines.

Immunol Res. 1999;20(2):101-8.

The immune system in the elderly: II. Specific cellular immunity.

Numerous changes occur in the immune system with advancing age, probably contributing to the decreased immunoresponsiveness in the elderly. These changes are often associated with important clinical manifestations such as increased susceptibility to infection and cancer frequently observed in the elderly population. Although both cellular and humoral immune responses are modified with advancing age, much of the decrease in immunoresponsiveness seen in elderly populations is associated with changes in T cell responses. The loss of effective immune activity is largely due to alterations within the T cell compartment which occur, in part, as a result of thymic involution. Substantial changes in both the functional and phenotypic profiles of T cells have been reported with advancing age. In fact, two prominent features of immunosenescence are altered T cell phenotype and reduced T cell response. One of the most consistent changes noted in T cells with advancing age is the decrease in the proportion of naive T cells with a concomitant increase in T cells with an activated/memory phenotype. In addition, there is evidence that the T cell population from aged individuals is hyporesponsive. The observed functional changes include decreased responsiveness to T cell receptor stimulation, impaired T cell proliferative capacity, a decline in the frequency of CD4+ T cells producing IL-2 and a decreased expression in IL-2 receptors. These latter findings probably explain the loss of proliferative capability of T cells from aged individuals. There is also evidence of a decrease in the early events of signal transduction, decreased activation-induced intracellular phosphorylation, and decreased cellular proliferative response to T cell receptor stimulation. The present review analyzes the main changes of the T cell compartment characterizing immunosenescence and discusses the possible mechanisms underlying these disregulations and their clinical implications.

Immunol Res. 1999;20(2):109-15.

The immune system in the elderly: III. Innate immunity.

The capability to cope with infectious agents and cancer cells resides not only in adaptive immune responses against specific antigens, mediated by T and B lymphocytes clonally distributed, but also in natural immune reactions. These innate defence mechanisms include chemotaxis, phagocytosis, natural cytotoxicity, cell interactions, and soluble mediators or cytokines. However, specific and natural immune mechanisms are always closely linked and interconnected, providing the primary defense against pathogens. The Authors discuss the main changes observed with advancing age in granulocytes and natural killer (NK) cell activity, in the expression and function of adhesion molecules, and in the pattern of cytokine production. Since phagocytic function is the primary mechanism through which the immune system eliminates most extracellular pathogenic microorganisms, analysis of this function is of clinical importance. Neutrophils from aged subjects often exhibit a diminished phagocytic capacity, as well as a depressed respiratory burst, notwithstanding an activated state. The activity of NK cells during aging has been studied extensively and different results have been reported. The most consistent data indicate an increase in cells with high NK activity with advancing age. Cells from healthy centenarians can efficiently kill target cells. This finding seems to suggest that innate immunity and in particular NK cell activity, is not heavily deteriorated with age. Conversely, a low NK activity is a predictor of impending morbidity. Immunosenescence is associated with increased expression of several cell adhesion molecules (CAM) resulting in an augmented capacity to adhere. Finally, also the cytokine network, responsible for differentiation, proliferation, and survival of lymphoid cells, undergoes complex changes with age. The main findings are a Th1 to Th2 cytokine production shift and an increased production of proinflammatory cytokines, which could explain many aspects of age-associated pathological events, such as atherosclerosis and osteoporosis.

Immunol Res. 1999;20(2):117-26.

Functions of natural killer cells.

Natural killer (NK) cells are effector lymphocytes of the innate immune system that control several types of tumors and microbial infections by limiting their spread and subsequent tissue damage. Recent research highlights the fact that NK cells are also regulatory cells engaged in reciprocal interactions with dendritic cells, macrophages, T cells and endothelial cells. NK cells can thus limit or exacerbate immune responses. Although NK cells might appear to be redundant in several conditions of immune challenge in humans, NK cell manipulation seems to hold promise in efforts to improve hematopoietic and solid organ transplantation, promote antitumor immunotherapy and control inflammatory and autoimmune disorders.

Nat Immunol. 2008 May;9(5):503-10.

CMV and Immunosenescence: from basics to clinics.

Alone among herpesviruses, persistent Cytomegalovirus (CMV) markedly alters the numbers and proportions of peripheral immune cells in infected-vs-uninfected people. Because the rate of CMV infection increases with age in most countries, it has been suggested that it drives or at least exacerbates “immunosenescence”. This contention remains controversial and was the primary subject of the Third International Workshop on CMV & Immunosenescence which was held in Cordoba, Spain, 15-16th March, 2012. Discussions focused on several main themes including the effects of CMV on adaptive immunity and immunosenescence, characterization of CMV-specific T cells, impact of CMV infection and ageing on innate immunity, and finally, most important, the clinical implications of immunosenescence and CMV infection. Here we summarize the major findings of this workshop.

Immun Ageing. 2012 Oct 31;9(1):23.

Distinct Responses of Cytotoxic Ganoderma lucidum Triterpenoids in Human Carcinoma Cells.

The medicinal mushroom Ganoderma lucidum is well recognized for its effective cancer-preventative and therapeutic properties, while specific components responsible for these anticancer effects are not well studied. Six triterpenoids that are ganolucidic acid E, lucidumol A, ganodermanontriol, 7-oxo-ganoderic acid Z, 15-hydroxy-ganoderic acid S, and ganoderic acid DM were isolated and identified from an extract of the mushroom. All compounds reduced cell growth in three human carcinoma cells (Caco-2, HepG2, and HeLa cells) dose dependently with LC50s from 20.87 to 84.36 µM. Moreover, the six compounds induced apoptosis in HeLa cells with a maximum increase (22%) of sub-G1 accumulations and 43.03% apoptotic cells in terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay (15-hydroxy-ganoderic acid S treatment). Apoptosis was further confirmed by annexin-V staining. Four of the compounds also caused apoptosis in Caco-2 cells with maximum 9.5% increase of sub-G1 accumulations (7-oxo-ganoderic acid Z treatment) and maximum 29.84% apoptotic cells in TUNEL assay (ganoderic acid DM treatment). Contrarily, none of the compounds induced apoptosis in HepG2 cells. The different responses of the three cell lines following these treatments indicated that the bioactive properties of these compounds may vary from cells of different sites of origin and are likely acting under diverse regulatory mechanisms.

Phytother Res. 2015 Nov;29(11):1744-52.

Immunosenescence of ageing.

Ageing is a complex process that negatively impacts the development of the immune system and its ability to function. The mechanisms that underlie these age-related defects are broad and range from defects in the haematopoietic bone marrow to defects in peripheral lymphocyte migration, maturation and function. The thymus is a central lymphoid organ responsible for production of naïve T cells, which play a vital role in mediating both cellular and humoral immunity. Chronic involution of the thymus gland is thought to be one of the major contributing factors to loss of immune function with increasing age. It has recently been demonstrated that thymic atrophy is mediated by a shift from a stimulatory to a suppressive cytokine microenvironment. In this review we present an overview of the morphological, cellular and biochemical changes that have been implicated in the decline of thymic and peripheral immune function with ageing. We conclude with the clinical implications of age-associated immunosenescence to vaccine development for tumours and infectious disease. A fundamental understanding of the complex mechanisms by which ageing attenuates immune function will enable translational research teams to develop new therapies and vaccines specifically aimed at overcoming these defects in immunological function in the aged.

J Pathol. 2007 Jan;211(2):144-56.

Interaction of ganoderic acid on HIV related target: molecular docking studies.

Finding the ultimate HIV cure remain a challenging tasks for decades. Various active compounds have been tested against various components of the virus in the effort to halt the virus development in infected host. The idea of finding cure from known pharmacologically active natural occurring compounds is intriguing and practical. Ganoderma lucidum (Ling-Zhi or Reishi) is one of the most productive and pharmacologically active compounds found in Asian countries. It has been used traditionally for many years throughout different cultures. More than a decade ago, el-Mekkawy and co-workers (1998) have tested several active compounds found in this plant. They have successfully identified several active compounds with reasonable inhibitory activity against HIV protease however; no further studies were done on these compounds. This study aimed to elucidate interactions for one of the active compounds of Ganoderma lucidum namely ganoderic acid with HIV-1 protease using molecular docking simulation. This study revealed four hydrogen bonds formed between model34 of ganoderic acid B and 1HVR. Hydrogen bonds in 1HVR-Model34 complex were formed through ILE50, ILE50’, ASP29 and ASP30 residues. Interestingly similar interactions were also observed in the native ligand in 1HVR. Furthermore, interactions involving ILE50 and ILE50’ residues have been previously identified to play central roles in HIV-1 protease-ligand interactions.These observed interactions not only suggested HIV-1 protease in general is a suitable target for ganoderic acid B, they also indicated a huge potential for HIV drug discovery based on this compound.

Bioinformation. 2011;7(8):413-7.

Muscle strength

Beta-hydroxy-beta-methylbutyrate (HMB) supplementation in humans is safe and may decrease cardiovascular risk factors.

The leucine metabolite, beta-hydroxy-beta-methylbutyrate (HMB) enhances the effects of exercise on muscle size and strength. Although several reports in animals and humans indicate that HMB is safe, quantitative safety data in humans have not been reported definitively. The objective of this work was to summarize safety data collected in nine studies in which humans were fed 3 g HMB/d. The studies were from 3 to 8 wk in duration, included both males and females, young and old, exercising or nonexercising. Organ and tissue function was assessed by blood chemistry and hematology; subtle effects on emotional perception were measured with an emotional profile test (Circumplex), and tolerance of HMB was assessed with a battery of 32 health-related questions. HMB did not adversely affect any surrogate marker of tissue health and function. The Circumplex emotion profile indicated that HMB significantly decreased (improved) one indicator of negative mood (Unactivated Unpleasant Affect category, P < 0.05). No untoward effects of HMB were indicated. Compared with the placebo, HMB supplementation resulted in a net decrease in total cholesterol (5.8%, P < 0.03), a decrease in LDL cholesterol (7.3%, P < 0.01) and a decrease in systolic blood pressure (4.4 mm Hg, P < 0.05). These effects of HMB on surrogate markers of cardiovascular health could result in a decrease in the risk of heart attack and stroke. In conclusion, the objective data collected across nine experiments indicate that HMB can be taken safely as an ergogenic aid for exercise and that objective measures of health and perception of well-being are generally enhanced.

J Nutr. 2000 Aug;130(8):1937-45.

Mechanism of the attenuation of proteolysis-inducing factor stimulated protein degradation in muscle by beta-hydroxy-beta-methylbutyrate.

The leucine metabolite beta-hydroxy-beta-methylbutyrate (HMB) prevents muscle protein degradation in cancer-induced weight loss through attenuation of the ubiquitin-proteasome proteolytic pathway. To investigate the mechanism of this effect, the action of HMB on protein breakdown and intracellular signaling leading to increased proteasome expression by the tumor factor proteolysis-inducing factor (PIF) has been studied in vitro using murine myotubes as a surrogate model of skeletal muscle. A comparison has been made of the effects of HMB and those of eicosapentaenoic acid (EPA), a known inhibitor of PIF signaling. At a concentration of 50 mumol/L, EPA and HMB completely attenuated PIF-induced protein degradation and induction of the ubiquitin-proteasome proteolytic pathway, as determined by the “chymotrypsin-like” enzyme activity, as well as protein expression of 20S proteasome alpha- and beta-subunits and subunit p42 of the 19S regulator. The primary event in PIF-induced protein degradation is thought to be release of arachidonic acid from membrane phospholipids, and this process was attenuated by EPA, but not HMB, suggesting that HMB might act at another step in the PIF signaling pathway. EPA and HMB at a concentration of 50 mumol/L attenuated PIF-induced activation of protein kinase C and the subsequent degradation of inhibitor kappaBalpha and nuclear accumulation of nuclear factor kappaB. EPA and HMB also attenuated phosphorylation of p42/44 mitogen-activated protein kinase by PIF, thought to be important in PIF-induced proteasome expression. These results suggest that HMB attenuates PIF-induced activation and increased gene expression of the ubiquitin-proteasome proteolytic pathway, reducing protein degradation.

Cancer Res. 2004 Dec 1;64(23):8731-5.

Attenuation of proteasome-induced proteolysis in skeletal muscle by {beta}-hydroxy-{beta}-methylbutyrate in cancer-induced muscle loss.

Loss of skeletal muscle is an important determinant of survival in patients with cancer-induced weight loss. The effect of the leucine metabolite beta-hydroxy-beta-methylbutyrate (HMB) on the reduction of body weight loss and protein degradation in the MAC16 model of cancer-induced weight loss has been compared with that of eicosapentaenoic acid (EPA), a recognized inhibitor of protein degradation. HMB was found to attenuate the development of weight loss at a dose greater than 0.125 g/kg accompanied by a small reduction in tumor growth rate. When EPA was used at a suboptimal dose level (0.6 g/kg) the combination with HMB seemed to enhance the anticachectic effect. Both treatments caused an increase in the wet weight of soleus muscle and a reduction in protein degradation, although there did not seem to be a synergistic effect of the combination. Proteasome activity, determined by the “chymotrypsin-like” enzyme activity, was attenuated by both HMB and EPA. Protein expression of the 20S alpha or beta subunits was reduced by at least 50%, as were the ATPase subunits MSS1 and p42 of the 19S proteasome regulatory subunit. This was accompanied by a reduction in the expression of E2(14k) ubiquitin-conjugating enzyme. The combination of EPA and HMB was at least as effective or more effective than either treatment alone. Attenuation of proteasome expression was reflected as a reduction in protein degradation in gastrocnemius muscle of cachectic mice treated with HMB. In addition, HMB produced a significant stimulation of protein synthesis in skeletal muscle. These results suggest that HMB preserves lean body mass and attenuates protein degradation through down-regulation of the increased expression of key regulatory components of the ubiquitin-proteasome proteolytic pathway, together with stimulation of protein synthesis.

Cancer Res. 2005 Jan 1;65(1):277-83.

b-Hydroxy-b-Methylbutyrate (HMB) Promotes Neurite Outgrowth in Neuro2a Cells.

b-Hydroxy-b-methylbutyrate (HMB) has been shown to enhance cell survival, differentiation and protein turnover in muscle, mainly activating phosphoinositide-3-kinase/protein kinase B (PI3K/Akt) and mitogen-activated protein kinases/ extracellular-signal-regulated kinases (MAPK/ERK) signaling pathways. Since these two pathways are related to neuronal survival and differentiation, in this study, we have investigated the neurotrophic effects of HMB in mouse neuroblastoma Neuro2a cells. In Neuro2a cells, HMB promotes differentiation to neurites independent from any effects on proliferation. These effects are mediated by activation of both the PI3K/Akt and the extracellular-signal-regulated kinases (ERK1/2) signaling as demonstrated by the use of specific inhibitors of these two pathways. As myocyte-enhancer factor 2 (MEF2) family of transcription factors are involved in neuronal survival and plasticity, the transcriptional activity and protein levels of MEF2 were also evaluated. HMB promoted MEF2-dependent transcriptional activity mediated by the activation of Akt and ERK1/2 pathways. Furthermore, HMB increases the expression of brain glucose transporters 1 (GLUT1) and 3 (GLUT3), and mTOR phosphorylation, which translates in a higher protein synthesis in Neuro2a cells. Furthermore, Torin1 and rapamycin effects on MEF2 transcriptional activity and HMB-dependent neurite outgrowth support that HMB acts through mTORC2. Together, these findings provide clear evidence to support an important role of HMB in neurite outgrowth.

PLoS One. 2015 Aug 12;10(8):e0135614.

Beta-hydroxy-beta-methylbutyrate ameliorates aging effects in the dendritic tree of pyramidal neurons in the medial prefrontal cortex of both male and female rats.

Beta-hydroxy-beta-methylbutyrate (HMB), a supplement commonly used to maintain muscle in elderly and clinical populations, has been unexplored in the aging brain. In both healthy aging humans and rat models, there are cognitive deficits associated with age-related dendritic shrinkage within the prefrontal cortex. The present study explores the effects of relatively short- and long-term (7 and 31 weeks) oral HMB supplementation starting at 12 months of age in male and female rats on the dendritic tree of layer 5 pyramidal neurons in the medial prefrontal cortex. Since female rats continue to secrete ovarian hormones after reaching reproductive senescence, middle-aged female rats were ovariectomized to model humans. As expected, there were fewer spines and a retraction of dendritic material in the apical and basilar trees in old age controls of both sexes compared with their middle-aged counterparts. However, these losses did not occur in the HMB-treated rats in either dendrites or the total number of dendritic spines. Thus, HMB forestalled the effects of aging on the dendritic tree of this population of neurons.

Neurobiol Aging. 2016 Apr;40:78-85.

A role for nutritional intervention in addressing the aging neuromuscular junction.

The purpose of this review is to discuss the structural and physiological changes that underlie age-related neuromuscular dysfunction and to summarize current evidence on the potential role of nutritional interventions on neuromuscular dysfunction-associated pathways. Age-related neuromuscular deficits are known to coincide with distinct changes in the central and peripheral nervous system, in the neuromuscular system, and systemically. Although many features contribute to the age-related decline in neuromuscular function, a comprehensive understanding of their integration and temporal relationship is needed. Nonetheless, many nutrients and ingredients show promise in modulating neuromuscular output by counteracting the age-related changes that coincide with neuromuscular dysfunction. In particular, dietary supplements, such as vitamin D, omega-3 fatty acids, b-hydroxy-b-methylbutyrate, creatine, and dietary phospholipids, demonstrate potential in ameliorating age-related neuromuscular dysfunction. However, current evidence seldom directly assesses neuromuscular outcomes and is not always in the context of aging. Additional clinical research studies are needed to confirm the benefits of dietary supplements on neuromuscular function, as well as to define the appropriate population, dosage, and duration for intervention.

Nutr Res. 2018 May;53:1-14.

Halt plaque

Pycnogenol® and Centella Asiatica for asymptomatic atherosclerosis progression.

AIM: The aim of the study was to evaluate the effect of the nutritional supplements Pycnogenol and TECA (total triterpenic fraction of Centella Asiatica) on atherosclerosis progression in low-risk asymptomatic subjects with carotid or femoral non-stenosing plaques. METHODS: This was an observational pilot substudy of the San Valentino epidemiological cardiovascular study. The study included 1363 subjects aged 45-60 without any conventional risk factors who had non stenosing atherosclerotic plaques (<50%) in at least one carotid or common femoral bifurcation, allocated into 6 groups: Group 1 (CONTROLS): management was based on education, exercise, diet and lifestyle changes. This same management plan was used in all groups; Group 2 Pycnogenol 50 mg/day; Group 3 Pycnogenol 100 mg/day; Group 4 Aspirin 100 mg/day or Ticlopidine 250 mg/day if intolerant to aspirin; Group 5 Aspirin 100 mg/day and Pycnogenol 100 mg/day; Group 6 Pycnogenol 100 mg/day plus TECA (total triterpenic fraction of Centella Asiatica) 100 mg/day. There was a six monthly follow-up up to 30 months. Plaque progression was assessed using the ultrasonic arterial score based on the arterial wall morphology and the number of plaques that progressed from the non-stenotic to the stenotic group. A secondary endpoint was to evaluate the changes in oxidative stress at baseline and at 30 months. RESULTS: The ultrasonic score increased significantly in groups 1, 2 and 4 but not in groups 3, 5 and 6 suggesting a beneficial effect of Pycnogenol 100 mg. The percentage of plaques that progressed from class IV to class V was 8.4% in group 2, 5.3% in group 3, 4% in group 5 and 1.1% in group 6 (P<0.0001) compared with 16.6% in group 4 (aspirin) and 21.3% in the control group suggesting a beneficial effect of Pycnogenol. The lowest rate of progression was in group 6 (Pycnogenol plus TECA). At 30 months, the oxidative stress in all the Pycnogenol groups was less than in the control group. The oxidative stress was lower in the Pycnogenol 100 mg group than the Pycnogenol 50 mg group (P<0.0001). In the combined group of Pycnogenol and TECA the oxidative stress was less than the Pycnogenol alone (P<0.001). CONCLUSION: Pycnogenol and the combination of Pycnogenol+TECA appear to reduce the progression of subclinical arterial lesions in low-risk asymptomatic subjects. The reduction in plaque progression was associated with a reduction in oxidative stress. The results justify a large randomized controlled study to demonstrate the efficacy of the combined Pycnogenol and TECA prophylactic therapy in subclinical atherosclerosis.

Int Angiol. 2014 Feb;33(1):20-6.

Variations in Echogenicity in Carotid and Femoral Atherosclerotic Plaques with Pycnogenol + Centella Asiatica Supplementation.

This registry study evaluated echogenicity of carotid-femoral plaques in asymptomatic subjects with increased oxidative stress and risk factors (mild hypertension, hypercholesterolemia). Supplementation with the combination Pycnogenol-CA (centella asiatica) on the echogenicity of plaques was assessed at 6 months (79 subjects). A standard management (SM) plan was used in all subjects (control of risk factors, lifestyle changes); 36 subjects used the supplements +SM; 43 SM only. The groups were comparable. High-resolution ultrasound evaluated echogenicity and plaque structure. Pycnogenol (150 mg/day) and CA (Centellicum, 450 mg/day) were used. At 6 months, cholesterol was reduced (p < 0.05) in both groups (difference between groups not significant). At 6 months, plasma free radicals were decreased with the supplements (17.64%; p  < 0.05; vs <2% in controls). The plaque stability index increased from 11.22;2.3 to 22.4;1.1 (p < 0.05) with the supplements; no significant changes were seen in controls. Plaque echogenicity (% of “whiter” component in images) increased with supplementation from 16.7;1.7% to 34.2;2% (p < 0.05); no variations were observed in controls. The maximum plaque height decreased (p < 0.05) with the supplements. No significant variations were observed in controls. Plaque length was decreased (p < 0.05) in the supplement group with no changes in controls. The number of plaques (carotid, femoral bifurcations) decreased with supplementation; no significant changes were observed in controls. No adverse events, tolerability problems, or variations in routine blood tests were recorded. The combination Pycnogenol-CA appears to improve echogenicity and stability of complex plaques in 6 months.

Int J Angiol. 2017 Jun;26(2):95-101.

Pycnogenol® and Centella asiatica to prevent asymptomatic atherosclerosis progression in clinical events.

BACKGROUND: The aim of this study was to evaluate the effect of the nutritional supplements Pycnogenol® and Centella asiatica (CA) on atherosclerosis progression in low-risk, asymptomatic subjects with carotid or femoral stenosing plaques. METHODS: The study included subjects aged 45-60 with stenosing atherosclerotic plaques (50-60%) in at least one carotid or common femoral bifurcation. Subjects were allocated into 3 groups. In Group 1 (controls), management was based on education, exercise, diet and lifestyle changes. This same management plan was used in the other two groups: Group 2 used Pycnogenol® (100 mg/day), while Group 3 used Pycnogenol® 100 mg/day plus CA (100 mg/day). The follow-up lasted 4 years. Plaque progression was assessed using the ultrasonic arterial score based on arterial wall morphology, considering plaque characteristics and the number of subjects that had cardiovascular events. Oxidative stress was also measured. RESULTS: Of the 413 individuals that were admitted, 391 individuals completed 4 years. Group distribution was comparable. The rate of progression of ultrasound arterial score was significantly lower in the two supplement groups (P<0.05) in comparison with controls suggesting a beneficial effect of Pycnogenol® with a significant difference in favor of the combination (P<0.05). There was a reduction in plaques progression in the supplement groups with the best effects obtained by the combination, considering maximum plaque thickness and length and echogenicity (grey scale median) (P<0.05). Plaques became generally dense (more echogenic) achieving a mixed echogenicity. The occurrence of anginal events was less than 3% in the two supplement groups (in comparison with 6.25% in controls) (P<0.05) with the best results obtained by the combination (P<0.05). The occurrence in myocardial infarctions was significantly lower for the combination (P<0.05). Minor transient ischemic attacks were also less frequent with the supplements with the best results observed with the combination (P<0.05). Events in controls - requiring hospital admission - were globally seen in 16.4% of subjects (minor events) in comparison with 8.9% of subjects using Pycnogenol® and only 3.3% of patients using the combination. At 4 years, oxidative stress in the supplement groups was lower than in controls (P<0.05, with no significant difference between groups 2 and 3). CONCLUSIONS: Pycnogenol® and the combination of Pycnogenol ® plus CA reduce the progression of arterial plaques and the progression to clinical stages. The reduction in plaques and clinical progression was associated with a reduction in oxidative stress. The results justify a larger study to define the efficacy of the combination of Pycnogenol® plus CA as a prophylaxis in preclinical atherosclerosis.

Minerva Cardioangiol. 2017 Feb;65(1):24-31.

Pycnogenol® and Centella asiatica in the management of asymptomatic atherosclerosis progression.

AIM: The aim of the study was to evaluate the effect of the nutritional supplements Pycnogenol® and total triterpenic fraction of Centella asiatica (TTFCA) on atherosclerosis progression in low-risk asymptomatic subjects with carotid or femoral stenosing plaques. METHODS: This was an observational pilot, substudy of the San Valentino epidemiological cardiovascular study. The study included 824 subjects aged 45-60 without any conventional risk factors who had a stenosing atherosclerotic plaque (>50-60%) in at least one carotid or common femoral bifurcation, allocated into 6 groups: Group 1 (Controls): management was based on education, exercise, diet and lifestyle changes. This same management plan was used in all other groups; group 2: Pycnogenol ® 50 mg/day; group 3: Pycnogenol® 100 mg/day; group 4: Aspirin® 100 mg/day or ticlopidine 250 mg/day if intolerant to aspirin; group 5: Aspirin® 100 mg/day and Pycnogenol ® 100 mg/day; group 6: Pycnogenol® 100 mg/day plus TTFCA 100 mg/day. The follow-up lasted 42 months. Plaque progression was assessed using the ultrasonic arterial score based on the arterial wall morphology and the number of plaques that progressed and on the number of subjects that had cardiovascular events. A secondary endpoint was to evaluate the changes in oxidative stress at baseline and at 42 months. RESULTS: The ultrasonic score increased significantly in groups 1, 2, and 4 (>1%) but not in groups 3, 5 and 6 (<1%) suggesting a beneficial effect of Pycnogenol® 100 mg. Considering the percent of patients that progressed from class V (asymptomatic) to VI (symptomatic) there was a progression of plaques in 48.09% of controls. In the Pycnogenol ® 100 (group 3, 10.4%) and in the Aspirin®+ Pycnogenol® (group 5, 10.68%) progression was half of what observed with antiplatelet agent (group 4, 20.93%); in the TTFCA+ Pycnogenol®group (group 6) progression was 7.4 times lower than in controls; 3.22 times lower than in the antiplatelet agents group (4). Events (hospital admission, specialized care) were observed in 16.03% of controls; there were 8.83% of subjects with events with Pycnogenol ® 50 mg and 8% in group 3 (Pycnogenol® 100 mg). In group 4 (antiplatelets), 8.52% of subjects had events; in group 5, 6.87% of subjects had events and in group 6 (TTFCA+ Pycnogenol®) only 4.41% had events (this was the lowest event rate; P<0.05). All treatment groups had a significantly lower event rate (P<0.05) in comparison with controls. Considering treatments groups 2, 3, 5, 6 had a lower number (P<0.05) of subjects in need of cardiovascular management in comparison with controls. The need for risk factor management was higher in controls and lower in group 6 (P<0.05). In groups 2 to 6 the need for risk factor management was lower than in controls (P<0.05). Including all events (hospital admission, need for treatment or for risk management) 51.9% of controls were involved. In the other groups there was a reduction (from a -9.28% reduction in group 2 to a -26% in group 6) (P<0.002). The most important reduction (higher that in all groups; P<0.05) was in group 6. At 42 months, oxidative stress in all the Pycnogenol® groups was less than in the control group. In the combined group of Pycnogenol® and TTFCA the oxidative stress was less than with Pycnogenol ® alone (P<0.001). CONCLUSION: Pycnogenol® and the combination of Pycnogenol® +TTFCA appear to reduce the progression of subclinical arterial plaques and the progression to clinical stages. The reduction in plaque and clinical progression was associated with a reduction in oxidative stress. The results justify a large, randomized, controlled study to demonstrate the efficacy of the combined Pycnogenol® and TTFCA prophylactic therapy in preclinical atherosclerosis.

Int Angiol. 2015 Apr;34(2):150-7.

Modification of the echogenicity of femoral plaques after treatment with total triterpenic fraction of Centella asiatica: a prospective, randomized, placebo-controlled trial.

The aim of this study was to evaluate whether TTFCA (total triterpenic fraction of Centella asiatica), was effective, by modulating collagen production, in a period of 12 months, increasing the echogenicity of echolucent plaques at the femoral bifurcation. Hypoechoic atherosclerotic plaques have been found to be associated with an increased evidence of cerebrovascular events. In this type of plaques stromal composition is limited as the collagen component is generally very low; the plaque composition is mainly due to lipid accumulation or thrombosis. The aim of this study was the evaluation of echogenicity of hyperechoic plaques and how it could be modified by a drug acting on the modulation of collagen synthesis. Antiplatelet agents were used in all patients; cholesterol-lowering agents were used in 34% of patients in the treatment group and in 36% in the placebo group. TTFCA was used at the dose of 60 mg thrice daily (oral tablets). Of the 60 included subjects 26 completed the study in the treatment group and 24 in the placebo group. At inclusion the average GSM in the treatment group was 14 (SD 3) and 14.3 (SD 3) in controls. At 12 months GSM was increased up to 22.8 (SD 4) in the treatment group and it was 15 (SD 3) in controls. Considering texture no significant changes were observed in controls while a qualitative increase in homogenicity was observed in the TTFCA group. Plaque size measured at the beginning and at the end of the study showed a median increase in size, in controls (23%; range 0%-44%); it was unchanged in the TTFCA group (variation 7%; 4%-26%). In conclusion in the treatment group plaques increased in echogenicity and in homogenicity; size and stenosis remained unchanged. Modulating the scarring process within echolucent plaques (low echogenicity, high echolucency, with a very low collagen/stromal component), possibly by collagen modulation, makes plaques more stable. This has been achieved and documented in the present study by an increase in the gray-scale median (plaques become more echogenic, more ‘white’). The variation in GSM is generally associated with a lower risk of wall thrombosis, rupture and embolization. These observations indicate a positive action of TTFCA on the stabilization of hypoechoic, low-density femoral plaques.

Angiology. 2001 Oct;52 Suppl 2:S69-73.

Increase in echogenicity of echolucent carotid plaques after treatment with total triterpenic fraction of Centella asiatica: a prospective, placebo-controlled, randomized trial.

The aim of this study was to evaluate whether total triterpenic fraction of Centella asiatica (TTFCA), was effective in modulating collagen production over 12 months, by producing an increase in echogenicity in echolucent carotid plaques. Part I was a pilot study aimed at evaluating the effects of TTFCA on different types of plaques. Part II was a prospective, randomized, placebo-controlled trial aimed at evaluating the effects of TTFCA on hypoechoic-echolucent plaques. The sonographic examination of carotid plaques was made with high-resolution ultrasound. Capturing, digital image processing, and normalization were standardized, interobserver, intrascanner, gain-level variability were standardized using as reference blood (black) for the most echolucent parts of the plaque and the adventitia (white) as the most echogenic part. Normalization of echo texture was obtained and plaque characterization differentiated echo-texture of plaque associated with events and those that did not cause embolization, thrombosis, or cardiovascular events. After identifying plaques at higher risk, patients were treated with TTFCA (oral tablets, 60 mg, thrice daily for 12 months) to evaluate whether this compound, by modulating collagen synthesis, could increase the echogenicity and therefore the stability of echolucent plaques. Part II was aimed at evaluating the effects of TTFCA on hypoechoic-echolucent plaques. Asymptomatic patients with echolucent plaques (GSM<18) were treated with TTFCA (60 mg, oral tablets three times daily for 12 months) or with comparable placebo after informed consent. All patients were also treated with antiplatelet agents. In part 1, at inclusion the GSC in the hypoechoic group was 15 (range, 12-18) while in the hyperechoic group it was 26 (range, 24-31); at 6 months it was increased in the hypoechoic group and at 12 months the increase was significant (19.5; p<0.05). There was a minor increase in GSM in the hyperechoic group (30; ns). In part II in the treatment group there was a significant difference in GSM (increase) at 12 months (p<0.05), improvement in texture (p<0.05) and a nonsignificant decrease in stenosis. No changes were observed in the placebo group. Events were observed in 6.5% of patients in the TTFCA group and in 11% in the control group (p<0.05). In conclusion these observations suggest a positive action of TTFCA on the stabilization of hypoechoic, low-density carotid plaques.

Angiology. 2001 Oct;52 Suppl 2:S19-25.

Breast cancer

Dietary polyphenols may affect DNA methylation.

Certain dietary polyphenols, such as (-)-epigallocatechin 3-gallate (EGCG) from green tea and genistein from soybean, have been demonstrated to inhibit DNA methyltransferases (DNMT) in vitro. This inhibitory activity is associated with the demethylation of the CpG islands in the promoters and the reactivation of methylation-silenced genes such as p16INK4a, retinoic acid receptor beta, O6-methylguanine methyltransferase, human mutL homolog 1, and glutathione S-transferase-pi. These activities have been observed in human esophageal, colon, prostate, and mammary cancer cell lines, and the activity can be enhanced by the presence of histone deacetylase inhibitors or by a longer-term treatment. Many other polyphenolic compounds have lower activities in inhibiting DNMT. Catechol polyphenols may indirectly inhibit DNMT by generating S-adenosyl-L-homocysteine on their methylation by S-adenosyl-L-methionine. In theory, prevention or reversal of hypermethylation-induced inactivation of key tumor suppression genes or receptor genes by DNMT inhibitors could be an effective approach for cancer prevention. Because of the rather low bioavailability of most polyphenolic compounds, how much of an effect dietary polyphenols would have on DNA methylation in humans is not clear. The effect of normal dietary consumption of a single polyphenolic compound is probably insignificant. However, the combination of polyphenols with dietary histone deacetylase inhibitors and the additive effect of different dietary chemicals may produce some effects. On the other hand, the consumption of excessive amounts of polyphenols in dietary supplements may affect DNA methylation status. All these possibilities remain to be examined.

J Nutr. 2007 Jan;137(1 Suppl):223S-228S.

Tea polyphenol (-)-epigallocatechin-3-gallate inhibits DNA methyltransferase and reactivates methylation-silenced genes in cancer cell lines.

Hypermethylation of CpG islands in the promoter regions is an important mechanism to silence the expression of many important genes in cancer. The hypermethylation status is passed to the daughter cells through the methylation of the newly synthesized DNA strand by 5-cytosine DNA methyltransferase (DNMT). We report herein that (-)-epigallocatechin-3-gallate (EGCG), the major polyphenol from green tea, can inhibit DNMT activity and reactivate methylation-silenced genes in cancer cells. With nuclear extracts as the enzyme source and polydeoxyinosine-deoxycytosine as the substrate, EGCG dose-dependently inhibited DNMT activity, showing competitive inhibition with a K(i) of 6.89 microM. Studies with structural analogues of EGCG suggest the importance of D and B ring structures in the inhibitory activity. Molecular modeling studies also support this conclusion, and suggest that EGCG can form hydrogen bonds with Pro(1223), Glu(1265), Cys(1225), Ser(1229), and Arg(1309) in the catalytic pocket of DNMT. Treatment of human esophageal cancer KYSE 510 cells with 5-50 microM of EGCG for 12-144 h caused a concentration- and time-dependent reversal of hypermethylation of p16(INK4a), retinoic acid receptor beta (RARbeta), O(6)-methylguanine methyltransferase (MGMT), and human mutL homologue 1 (hMLH1) genes as determined by the appearance of the unmethylation-specific bands in PCR. This was accompanied by the expression of mRNA of these genes as determined by reverse transcription-PCR. The re-expression of RARbeta and hMLH1 proteins by EGCG was demonstrated by Western blot. Reactivation of some methylation-silenced genes by EGCG was also demonstrated in human colon cancer HT-29 cells, esophageal cancer KYSE 150 cells, and prostate cancer PC3 cells. The results demonstrate for the first time the inhibition of DNA methylation by a commonly consumed dietary constituent and suggest the potential use of EGCG for the prevention or reversal of related gene-silencing in the prevention of carcinogenesis.

Cancer Res. 2003 Nov 15;63(22):7563-70.

A novel prodrug of epigallocatechin-3-gallate: differential epigenetic hTERT repression in human breast cancer cells.

Epigallocatechin-3-gallate (EGCG), a major component of green tea polyphenols (GTP), has been reported to downregulate telomerase activity in breast cancer cells thereby increasing cellular apoptosis and inhibiting cellular proliferation. However, the major concerns with GTPs are their bioavailability and stability under physiologic conditions. In the present study, we show that treatments with EGCG and a novel prodrug of EGCG (pro-EGCG or pEGCG) dose- and time-dependently inhibited the proliferation of human breast cancer MCF-7 and MDA-MB-231 cells but not normal control MCF10A cells. Furthermore, both EGCG and pro-EGCG inhibited the transcription of hTERT (human telomerase reverse transcriptase), the catalytic subunit of telomerase, through epigenetic mechanisms in estrogen receptor (ER)-positive MCF-7 and ER-negative MDA-MB-231 cells. The downregulation of hTERT expression was found to be because of hTERT promoter hypomethylation and histone deacetylations, mediated at least partially through inhibition of DNA methyltransferase and histone acetyltransferase activities, respectively. In addition, we also observed that EGCG and pEGCG can remodel chromatin structures of the hTERT promoter by decreasing the level of acetyl-H3, acetyl-H3K9, and acetyl-H4 to the hTERT promoter. EGCG and pEGCG induced chromatin alterations that facilitated the binding of many hTERT repressors such as MAD1 and E2F-1 to the hTERT regulatory region. Depletion of E2F-1 and MAD1 by using siRNA reversed the pEGCG downregulated hTERT expression and associated cellular apoptosis differently in ER-positive and ER-negative breast cancer cells. Collectively, our data provide new insights into breast cancer prevention through epigenetic modulation of telomerase by using pro-EGCG, a more stable form of EGCG, as a novel chemopreventive compound.

Cancer Prev Res (Phila). 2011 Aug;4(8):1243-54.

Dietary sulforaphane, a histone deacetylase inhibitor for cancer prevention.

The reversible acetylation of histones is an important mechanism of gene regulation. During prostate cancer progression, specific modifications in acetylation patterns on histones are apparent. Targeting the epigenome, including the use of histone deacetylase (HDAC) inhibitors, is a novel strategy for cancer chemoprevention. Recently, drugs classified as HDAC inhibitors have shown promise in cancer clinical trials. We have previously found that sulforaphane (SFN), a compound found in cruciferous vegetables, inhibits HDAC activity in human colorectal and prostate cancer cells. Based on the similarity of SFN metabolites and other phytochemicals to known HDAC inhibitors, we previously demonstrated that sulforaphane acted as an HDAC inhibitor in the prostate, causing enhanced histone acetylation, derepression of P21 and Bax, and induction of cell cycle arrest/apoptosis, leading to cancer prevention. The ability of SFN to target aberrant acetylation patterns, in addition to effects on phase 2 enzymes, may make it an effective chemoprevention agent. These studies are important because of the potential to qualify or change recommendations for high-risk prostate cancer patients and thereby increase their survival through simple dietary choices incorporating easily accessible foods into their diets. These studies also will provide a strong scientific foundation for future large-scale human clinical intervention studies.

J Nutr. 2009 Dec;139(12):2393-6.

Inhibition of carcinogenesis by dietary polyphenolic compounds.

Plants consumed by humans contain thousands of phenolic compounds. The effects of dietary polyphenols are of great current interest due to their antioxidative and possible anticarcinogenic activities. A popular belief is that dietary polyphenols are anticarcinogens because they are antioxidants, but direct evidence for this supposition is lacking. This chapter reviews the inhibition of tumorigenesis by phenolic acids and derivatives, tea and catechins, isoflavones and soy preparations, quercetin and other flavonoids, resveratrol, and lignans as well as the mechanisms involved based on studies in vivo and in vitro. Polyphenols may inhibit carcinogenesis by affecting the molecular events in the initiation, promotion, and progression stages. Isoflavones and lignans may influence tumor formation by affecting estrogen-related activities. The bioavailability of the dietary polyphenols is discussed extensively, because the tissue levels of the effective compounds determine the biological activity. Understanding the bioavailability and blood and tissue levels of polyphenols is also important in extrapolating results from studies in cell lines to animal models and humans. Epidemiological studies concerning polyphenol consumption and human cancer risk suggest the protective effects of certain food items and polyphenols, but more studies are needed for clear-cut conclusions. Perspectives on the application of dietary polyphenols for the prevention of human cancer and possible concerns on the consumption of excessive amounts of polyphenols are discussed.

Annu Rev Nutr. 2001;21:381-406.

Sulforaphane causes epigenetic repression of hTERT expression in human breast cancer cell lines.

BACKGROUND: Sulforaphane (SFN), an isothiocyanate found in cruciferous vegetables, is a common dietary component that has histone deacetylase inhibition activity and exciting potential in cancer prevention. The mechanisms by which SFN imparts its chemopreventive properties are of considerable interest and little is known of its preventive potential for breast cancer. PRINCIPAL FINDINGS: We found that SFN significantly inhibits the viability and proliferation of breast cancer cells in vitro while it has negligible effects on normal breast cells. Inhibition of telomerase has received considerable attention because of its high expression in cancer cells and extremely low level of expression in normal cells. SFN treatment dose- and time-dependently inhibited human telomerase reverse transcriptase (hTERT), the catalytic regulatory subunit of telomerase, in both MCF-7 and MDA-MB-231 human breast cancer cells. DNA methyltransferases (DNMTs), especially DNMT1 and DNMT3a, were also decreased in SFN-treated breast cancer cells suggesting that SFN may repress hTERT by impacting epigenetic pathways. Down-regulation of DNMTs in response to SFN induced site-specific CpG demethylation occurring primarily in the first exon of the hTERT gene thereby facilitating CTCF binding associated with hTERT repression. Chromatin immunoprecipitation (ChIP) analysis of the hTERT promoter revealed that SFN increased the level of active chromatin markers acetyl-H3, acetyl-H3K9 and acetyl-H4, whereas the trimethyl-H3K9 and trimethyl-H3K27 inactive chromatin markers were decreased in a dose-dependent manner. SFN-induced hyperacetylation facilitated the binding of many hTERT repressor proteins such as MAD1 and CTCF to the hTERT regulatory region. Depletion of CTCF using siRNA reduced the SFN-induced down-regulation of hTERT mRNA transcription in these breast cancer cells. In addition, down-regulation of hTERT expression facilitated the induction of cellular apoptosis in human breast cancer cells. SIGNIFICANCE: Collectively, our results provide novel insights into SFN-mediated epigenetic down-regulation of telomerase in breast cancer prevention and may open new avenues for approaches to SFN-mediated cancer prevention.

PLoS One. 2010 Jul 6;5(7):e11457.

Sulforaphane induces cell type-specific apoptosis in human breast cancer cell lines.

Sulforaphane, an isothiocyanate found in cruciferous vegetables, has been shown to induce phase 2 detoxication enzymes and inhibit the growth of chemically induced mammary tumors in rats, although the exact mechanisms of action of sulforaphane are not understood. In this study, we evaluated the effects of sulforaphane on cell growth and death in several human breast cancer cell lines and examined the hypothesis that sulforaphane acts as a histone deacetylase (HDAC) inhibitor in these cell lines. Sulforaphane treatment inhibited cell growth, induced a G(2)-M cell cycle block, increased expression of cyclin B1, and induced oligonucleosomal DNA fragmentation in the four human breast cancer cell lines examined, MDA-MB-231, MDA-MB-468, MCF-7, and T47D cells. Activation of apoptosis by sulforaphane in MDA-MB-231 cells seemed to be initiated through induction of Fas ligand, which resulted in activation of caspase-8, caspase-3, and poly(ADP-ribose) polymerase, whereas apoptosis in the other breast cancer cell lines was initiated by decreased Bcl-2 expression, release of cytochrome c into the cytosol, activation of caspase-9 and caspase-3, but not caspase-8, and poly(ADP-ribose) polymerase cleavage. Sulforaphane inhibited HDAC activity and decreased the expression of estrogen receptor-alpha, epidermal growth factor receptor, and human epidermal growth factor receptor-2 in each cell line, although no change in the acetylation of H3 or H4 was seen. These data suggest that sulforaphane inhibits cell growth, activates apoptosis, inhibits HDAC activity, and decreases the expression of key proteins involved in breast cancer proliferation in human breast cancer cells. These results support testing sulforaphane in vivo and warrant future studies examining the clinical potential of sulforaphane in human breast cancer.

Mol Cancer Ther. 2007 Mar;6(3):1013-21.