Life Extension Magazine®

Issue: Aug 2017

Homocysteine, Erectile dysfunction, Skin care, and Blood sugar

Homocysteine, Erectile dysfunction, Skin care, and Blood sugar


High homocysteine and low folate plasma concentrations are associated with cardiovascular events but not bleeding during warfarin treatment.

BACKGROUND: Previous studies have shown that homocysteine and folate levels in plasma are associated with risk for cardiovascular events and mortality. The aim of this study was to investigate if plasma concentrations of total homocysteine and folate can predict major bleeding, cardiovascular events, and all-cause mortality in patients being treated with warfarin. METHODS: In a longitudinal cohort study, 719 patients who were taking warfarin were followed for 3,001 treatment years. The following were recorded and classified: major bleeding; cardiovascular events including stroke, arterial emboli, and myocardial infarction (MI); and mortality. Blood samples collected at baseline were analysed for plasma homocysteine and folate levels. RESULTS: After adjustment for age, C-reactive protein, and creatinine, high homocysteine levels were associated with cardiovascular events [hazard ratio (HR) 1.23 per standard deviation (SD); 95% confidence interval (CI): 1.03-1.47], MI (HR 1.38 per SD; 95% CI: 1.03-1.85), and all-cause mortality (HR 1.41 per SD; 95% CI: 1.19-1.68). The highest tertile of folate compared to the lowest tertile was associated with decreased risk for both cardiovascular events (HR 0.64; 95% CI: 0.43-0.91) and MI (HR 0.45; 95% CI: 0.21-0.97). There was no association between major bleeding and homocysteine or folate levels. CONCLUSIONS: In patients receiving warfarin treatment, high homocysteine and low folate plasma concentrations are associated with increased risk for cardiovascular events but not major bleeding. For homocysteine levels, there is also an association with all-cause mortality.

Clin Chem Lab Med. 2016 Dec 1;54(12):1981-1986

Homocysteine and Its Relationship to Asymptomatic Carotid Stenosis in a Chinese Community Population.

Little is known about the association between homocysteine (Hcy) and asymptomatic CAS in the healthy population. The purpose of this study was to investigate the relationship between Hcy levels and asymptomatic CAS in a Chinese community population. The current study included 5,393 participants who were age of 40 years or older, and free of stroke, transient ischemic attack, and coronary artery disease. Demographic and clinical variables were investigated, and the presence of CAS was assessed by Color Doppler Ultrasound. A multivariate logistic regression was used to examine the association between Hcy levels and asymptomatic CAS. 361 (6.69%) participants were diagnosed with asymptomatic CAS, who had higher Hcy levels compared with those without (p-value for trend = 0.0001). After adjusting other possible risk factors, Hcy > 19.3µmol/L was considered as an independent indicator of asymptomatic CAS (OR 1.53, 95%CI 1.05-2.23; p-value for trend = 0.0265), but with a difference between participants with diabetes and without [OR (95%CI): 2.89(1.02-8.22) vs. 1.42(0.95-2.12); P interaction < 0.05]. In this large-population, community-based study, Hcy is an independent indicator of asymptomatic CAS, especially in patients with diabetes

Sci Rep. 2016 Nov 21;6:37361.

Homocysteine and thrombosis: from basic science to clinical evidence.

Homocysteine is a sulfhydryl-containing amino acid formed during the metabolism of methionine. Rapidly accumulating evidence links elevated homocysteine levels to thrombosis via several mechanisms such as increased tissue factor expression, attenuated anticoagulant processes, enhanced platelet reactivity, increased thrombin generation, augmented factor V activity, impaired fibrinolytic potential, and vascular injury, including endothelial dysfunction. Molecular mechanisms underlying prothrombotic actions of homocysteine are incompletely understood and involve oxidative stress, DNA hypomethylation, and proinflammatory effects. Current evidence from retrospective and prospective studies supports the concept that higher total plasma homocysteine concentration is associated with increased risk of coronary artery disease, stroke, and venous thromboembolism. Hyperhomocysteinemia is currently considered a relatively weak prothrombotic factor. It is still unclear whether administration of vitamins, that reduce homocysteine levels acting as cofactors of the enzymes involved in the methionine metabolism, may decrease the risk of arterial and/or venous thromboembolic events. Ongoing clinical trials might help clarify this issue.

Thromb Haemost. 2005 Nov;94(5):907-15

Comparison of the effect of low-dose supplementation with L-5-methyltetrahydrofolate or folic acid on plasma homocysteine: a randomized placebo-controlled study.

BACKGROUND: Food fortification with folic acid has been introduced in several countries for the prevention of neural tube defects. Fortification has lowered total homocysteine (tHcy) concentrations in the US population, a consequence that may have health benefits. However, folic acid fortification could mask vitamin B-12 deficiency. Synthetic L-5-methyltetrahydrofolate (L-MTHF) may be more appropriate than folic acid as a fortificant because it is unlikely to mask the hematologic indicators of vitamin B-12 deficiency. OBJECTIVE: The objective of the study was to compare the effectiveness of 100 micro g folic acid/d with that of equimolar L-MTHF in lowering tHcy in healthy volunteers. DESIGN: The study was designed as a 24-wk, randomized, placebo-controlled intervention. Free-living healthy volunteers (n = 167) were randomly assigned to receive a daily supplement containing folic acid (100 microg), L-MTHF (113 microg), or placebo. Blood collected at baseline and at 8, 16, and 24 wk was analyzed for tHcy, plasma folate, and red blood cell folate (RCF) concentrations. RESULTS: At 24 wk, after adjustment for baseline values, mean (95% CI) tHcy was 14.6% (9.3, 19.5%) and 9.3% (3.7, 14.6%) lower, mean plasma folate was 34% (14, 56%) and 52% (30, 78%) higher, and mean RCF was 23% (12, 35%) and 31% (19, 44%) higher in the L-MTHF and folic acid groups, respectively, than in the placebo group. L-MTHF was more effective than was folic acid in lowering tHcy (P < 0.05). At 24 wk, the increases in plasma folate and RCF concentrations did not differ significantly between the 2 supplemented groups. CONCLUSION: Low-dose L-MTHF is at least as effective as is folic acid in reducing tHcy concentrations in healthy persons.

Am J Clin Nutr. 2003 Mar;77(3):658-62

Nutrition and stroke prevention.

Nutrition is much more important in prevention of stroke than is appreciated by most physicians. The powerful effects of statin drugs in lowering the levels of fasting cholesterol, combined with an unbalanced focus on fasting lipids (as opposed to postprandial fat and oxidative stress), have led many physicians and patients to believe that diet is relatively unimportant. Because the statins can lower fasting lipids by &50% to 60%, and a low-fat diet only lowers fasting cholesterol by &5% to 10%, this error is perhaps understandable. However, a Cretan Mediterranean diet, which is high in beneficial oils, whole grains, fruits, and vegetables and low in cholesterol and animal fat, has been shown to reduce stroke and myocardial infarction by 60% in 4 years compared with the American Heart Association diet. This effect is twice that of simvastatin in the Scandinavian Simvastatin Survival Study: a reduction of myocardial infarction by 40% in 6 years. Vitamins for lowering of homocysteine may yet be shown to be beneficial for reduction of stroke; a key issue is the high prevalence of unrecognized deficiency of vitamin B(12), requiring higher doses of vitamin B(12) than have been used in clinical trials to date. Efforts to duplicate with supplementation the evidence of benefit for vitamins E, C, and beta carotene have been largely fruitless. This may be related to the broad combination of antioxidants included in a healthy diet. A Cretan Mediterranean diet is probably more effective because it provides a wide range of antioxidants from fruits and vegetables of all colors.

Stroke. 2006 Sep;37(9):2430-5

Cardiovascular risk factors and inflammatory activity among centenarians with and without dementia.

A better knowledge of the differences existing between individuals who maintain cognition up to 100 years of age or more and those of the same age who present dementia syndrome may be of help in understanding the dementia of the very elderly people. The aim of this study was to assess cardiovascular risk factors and inflammatory markers among centenarians with and without dementia. A population-based cross-sectional study was conducted on centenarians residing in a middle-size city. Volunteers were evaluated by comprehensive geriatric assessment at home. General laboratory examinations were performed and cardiovascular risk and inflammatory activity markers were determined. Mean subject age was 101 ± 2 years, and 82% were women. Assessment of dementia syndrome revealed that 36.4% of the centenarians had preserved cognition. Centenarians with dementia had lower schooling (p < 0.01), lower body mass index (p = 0.02) and higher homocysteine levels (p < 0.01) and tended to have a lower systolic blood pressure (p = 0.05). Regarding the markers of inflammatory activity, demented subjects had high levels of interleukin-6 (p < 0.01), high-sensitivity C-reactive protein (p = 0.02), and erythrocyte sedimentation rate (p = 0.01) and lower albumin levels (p = 0.02) compared to centenarians without dementia. Concluding, centenarians with preserved cognition had better nutritional status, lower homocysteinemia, tendency to higher blood pressure and lower inflammatory activity compared to demented subjects.

Aging Clin Exp Res. 2017 Jun;29(3):411-417

Predicting Risk of Cognitive Decline in Very Old Adults Using Three Models: The Framingham Stroke Risk Profile; the Cardiovascular Risk Factors, Aging, and Dementia Model; and Oxi-Inflammatory Biomarkers.

OBJECTIVES: To examine the Framingham Stroke Risk Profile (FSRP); the Cardiovascular Risk Factors, Aging, and Incidence of Dementia (CAIDE) risk score, and oxi-inflammatory load (cumulative risk score of three blood biomarkers-homocysteine, interleukin-6, C-reactive protein) for associations with cognitive decline using three cohort studies of very old adults and to examine whether incorporating these biomarkers with the risk scores can affect the association with cognitive decline. DESIGN: Three longitudinal, population-based cohort studies. SETTING: Newcastle-upon-Tyne, United Kingdom; Leiden, the Netherlands; and Lakes and Bay of Plenty District Health Board areas, New Zealand. PARTICIPANTS: Newcastle 85+ Study participants (n = 616), Leiden 85-plus Study participants (n = 444), and Life and Living in Advanced Age, a Cohort Study in New Zealand (LiLACS NZ Study) participants (n = 396). MEASUREMENTS: FSRP, CAIDE risk score, oxi-inflammatory load, FSRP incorporating oxi-inflammatory load, and CAIDE risk score incorporating oxi-inflammatory load. Oxi-inflammatory load could be calculated only in the Newcastle 85+ and the Leiden 85-plus studies. Measures of global cognitive function were available for all three data sets. Domain-specific measures were available for the Newcastle 85+ and the Leiden 85-plus studies. RESULTS: Meta-analysis of pooled results showed greater risk of incident global cognitive impairment with higher FSRP (hazard ratio (HR) = 1.46, 95% confidence interval (CI) = 1.08-1.98), CAIDE (HR = 1.53, 95% CI = 1.09-2.14), and oxi-inflammatory load (HR = 1.73, 95% CI = 1.04-2.88) scores. Adding oxi-inflammatory load to the risk scores increased the risk of cognitive impairment for the FSRP (HR = 1.65, 95% CI = 1.17-2.33) and the CAIDE model (HR = 1.93, 95% CI = 1.39-2.67). CONCLUSION: Adding oxi-inflammatory load to cardiovascular risk scores may be useful for determining risk of cognitive impairment in very old adults.

J Am Geriatr Soc. 2017 Feb;65(2):381-389

Elevated Homocysteine Level Related to Poor Outcome After Thrombolysis in Acute Ischemic Stroke.

BACKGROUND Hyperhomocy-steinemia (HHcy) is a well-known risk factor for ischemic stroke. However, whether HHcy can influence the treatment outcome of acute ischemic stroke (AIS) patients has yet to be fully determined. In this study, we investigated the relationship between serum homocysteine (Hcy) level and prognosis in AIS patients who received tissue plasminogen activator (tPA) treatment. MATERIAL AND METHODS Patients were recruited according to the research criteria and grouped by their serum Hcy levels. Neurological outcome was evaluated by National Institute of Health Stroke Scale (NIHSS) score system before and 1 week after treatment, and functional outcome was evaluated by modified Rankin Scale (MRS) score system after 3 months. All patients took CT/MRI examination to detect cerebral hemorrhage in 24 hours after tPA treatment. Receiver operating characteristic curve (ROC) was employed to assess if serum homocysteine level can be used as an index to predict the outcome after tPA treatment. RESULTS The mean (±SD) serum Hcy level of 194 patients was 22.62±21.23 µmol/L. After 1-week tPA treatment, the NIHSS scores of high Hcy level group were significantly higher than those of low level group (p<0.05), meantime the high Hcy group showed obvious symptomatic intracerebral hemorrhage risk after 24 hours (p<0.05). Poor outcome was presented in mRS score results after 3 months in high Hcy level group, which compared with low Hcy level group (p<0.01). The ROC showed that Hcy level was a moderately sensitive and specific index to predict the prognosis with an optimal cut-off value at 19.95 µmol/L (sensitivity [58.2%], specificity [80.3%]). CONCLUSIONS High serum homocysteine level could potentially predict poor prognosis in acute ischemic stroke patients after tPA treatment.

Med Sci Monit. 2016 Sep 15;22:3268-73

Erectile dysfunction

Male sexual dysfunction and infertility associated with neurological disorders.

Normal sexual and reproductive functions depend largely on neurological mechanisms. Neurological defects in men can cause infertility through erectile dysfunction, ejaculatory dysfunction and semen abnormalities. Among the major conditions contributing to these symptoms are pelvic and retroperitoneal surgery, diabetes, congenital spinal abnormalities, multiple sclerosis and spinal cord injury. Erectile dysfunction can be managed by an increasingly invasive range of treatments including medications, injection therapy and the surgical insertion of a penile implant. Retrograde ejaculation is managed by medications to reverse the condition in mild cases and in bladder harvest of semen after ejaculation in more severe cases. Anejaculation might also be managed by medication in mild cases while assisted ejaculatory techniques including penile vibratory stimulation and electroejaculation are used in more severe cases. If these measures fail, surgical sperm retrieval can be attempted. Ejaculation with penile vibratory stimulation can be done by some spinal cord injured men and their partners at home, followed by in-home insemination if circumstances and sperm quality are adequate. The other options always require assisted reproductive techniques including intrauterine insemination or in vitro fertilization with or without intracytoplasmic sperm injection. The method of choice depends largely on the number of motile sperm in the ejaculate.

Asian J Androl. 2012 Jan;14(1):61-8

Obesity, low testosterone levels and erectile dysfunction.

Obesity is an important risk factor for many common diseases including cardiovascular disease (CVD), type 2 diabetes, cancer and erectile dysfunction (ED). Adipose tissues produce a number of adipokines and cytokines, which affect endothelial and metabolic function resulting in insulin resistance and the metabolic syndrome (risks factors for CVD). Both ED and metabolic syndrome improve with a reduction in body mass index (BMI). The relationships among obesity, metabolic syndrome, ED, sex hormone-binding globulin (SHBG) and serum total and free testosterone levels are complex and often confusing to the physician. It is known that BMI is inversely proportional to serum total testosterone concentrations; low serum SHBG levels in obesity contribute to the low serum total testosterone. Recent studies show that BMI is also inversely proportional to free testosterone concentration. The characteristic low serum testosterone concentrations observed in obese men are also present in men with the metabolic syndrome and type 2 diabetes mellitus. A small proportion of men with ED have hypogonadism; however, the proportion increases if these men are obese with manifestations of the metabolic syndrome or type 2 diabetes mellitus. ED is a common symptom in patients with type 2 diabetes who also have low testosterone levels. This review describes the relationships between low serum testosterone concentrations and ED in obese patients and those with metabolic syndrome and type 2 diabetes mellitus.

Int J Impot Res. 2009 Mar-Apr;21(2):89-98

Antidepressant-induced sexual dysfunction.

OBJECTIVE: To review the evidence regarding antidepressant-induced sexual dysfunction and address implications for treatment strategy and health plan coverage policies for antidepressant medications. DATA SOURCES: Primary articles were identified by a MEDLINE and HealthSTAR search to identify English-language studies published between January 1986 and July 2000. Search terms included sexual dysfunction or sexual function and antidepressants, fluoxetine, sertraline, paroxetine, fluvoxamine, citalopram, venlafaxine, nefazodone, bupropion, and mirtazapine. A cross-check of references cited in 10 published reviews yielded additional in-scope articles. STUDY SELECTION AND DATA EXTRACTION: Approximately 200 articles were identified, including 8 randomized controlled trials and numerous open-label studies, case series, and case reports. Of the randomized controlled trials, only 5 were designed to evaluate the incidence of sexual dysfunction associated with antidepressant treatment. Three additional randomized controlled trials included a structured assessment of sexual dysfunction within an efficacy trial. Data extraction excluded case reports, letters, and other limited study designs. A panel survey augmented published reports. DATA SYNTHESIS: Sexual dysfunction is a relatively common adverse effect of many of the antidepressants in common use today. Rates of sexual dysfunction observed in clinical practice may be higher than those reported in the product information for several agents. Selective serotonin-reuptake inhibitors (SSRIs) appear to be the class of antidepressants most likely to cause sexual dysfunction. Published studies suggest that between 30% and 60% of SSRI-treated patients may experience some form of treatment-induced sexual dysfunction. Bupropion and nefazodone appear to be much less likely to cause sexual dysfunction (<or=10% of patients). Mirtazapine also appears to be associated with a low rate of sexual adverse effects. Panel results largely reflect the consensus of the literature. CONCLUSIONS: Sexual dysfunction is a common adverse effect of antidepressant treatment. Physicians should monitor their patients for antidepressant-induced sexual adverse effects, as these may affect compliance with therapy and ultimate treatment success. In addition to the consequences for patient health and well-being, managed-care organizations should be concerned with sexually related adverse effects of antidepressants, insofar as additional healthcare resources may be required to treat depressed patients in whom these adverse effects arise.

Ann Pharmacother. 2002 Oct;36(10):1577-89

Sildenafil citrate for erectile dysfunction in men with diabetes and cardiovascular risk factors: a retrospective analysis of pooled data from placebo-controlled trials.

Cardiovascular (CV) risk factors are associated with an increased risk of erectile dysfunction (ED). In men with diabetes mellitus (DM), pooled from clinical trials of sildenafil treatment for ED, this retrospective analysis determined efficacy and safety, overall and in subgroups with additional CV risk (i.e., hypertension, dyslipidemia, and smoking). RESEARCH DESIGN AND METHODS: From the manufacturer's database of worldwide research, 12-week data from men with DM were pooled from randomized, double-blind, placebo-controlled trials of flexible-dose sildenafil (25, 50, or 100 mg, PRN) for ED. MAIN OUTCOME MEASURES: Question 3 (achieving an erection), question 4 (maintaining an erection), and the Erectile Function domain of the International Index of Erectile Function; percentage of successful intercourse attempts according to patient event logs; and response to a global efficacy question (GEQ). Differences between groups were determined using logistic regression (percentage of responders according to GEQ) and analysis of covariance (all other outcomes). RESULTS: Inclusion criteria were met by 11 trials and by 974 men with DM and ED who were randomized to placebo (n = 482) and sildenafil (n = 492) within the selected trials. For all outcomes, overall and regardless of additional CV risk, the benefit was greater for sildenafil versus placebo (p < or = 0.0001), including 3-fold more men responding that sildenafil treatment improved their erections (62% vs. 18%) and a more than doubling of the mean +/- standard error percentage of successful sexual intercourse attempts (52.6 +/- 5.0 vs. 22.4 +/- 5.1). Adverse events were mild to moderate and included (sildenafil vs. placebo) headache (5% vs. 2%), flushing (7% vs. 2%), and dyspepsia (4% vs. 0%), which is consistent with the profile in the general population of men treated with sildenafil for ED. CONCLUSION: This retrospective analysis of pooled data showed that sildenafil was well tolerated and improved erectile function and intercourse success in men with ED and DM, regardless of additional CV risk factors.

Curr Med Res Opin. 2006 Nov;22(11):2111-20

Non-arteritic anterior ischemic optic neuropathy (NAION) and phosphodiesterase type-5 inhibitors.

OBJECTIVE: To determine whether a causative relationship exists between non-arteritic anterior ischemic optic neuropathy (NAION) and the use of phosphodiesterase-5 (PDE-5) inhibitors for the treatment of erectile dysfunction. METHODS: A comprehensive review of the literature was performed to identify the contemporary understanding of NAION pathophysiology, epidemiology, and occurrence in men using the oral PDE-5 inhibitors sildenafil (Viagra, Pfizer), vardenafil (Levitra, Bayer AG), and tadalafil (Cialis, Lilly-ICOS LLC) for the treatment of erectile dysfunction. RESULTS: NAION is the second most common acquired optic neuropathy in men aged 50 years and older. Risk factors for NAION, cardiovascular disease, and erectile dysfunction are shared and include age, dyslipidemia, diabetes, hypertension, and cigarette smoking. To date, less than 50 cases of NAION associated with PDE-5 use have been reported to the United State's Food and Drug Administration (FDA) and five Canadian cases alerted to Health Canada. Given the large number of men safely using these agents and a limited number of events, it is not possible to determine whether NAION is directly linked to the use of PDE-5 inhibitors, underlying cardiovascular risk factors, ocular anatomical defects, a combination of these variables, or as yet unidentified factors. CONCLUSIONS: PDE-5 inhibitors have gained widespread use for the treatment of erectile dysfunction due to their safety, efficacy, and ease of use. Their role in the pathogenesis of NAION remains controversial. Reasonable and informed consent regarding the possible but low risk of NAION with the use of sildenafil, vardenafil and tadalafil is recommended. Loss or decreased vision, whether painful or painless, demands urgent patient assessment and immediate cessation of PDE-5 inhibitor use.

Can J Urol. 2006 Oct;13(5):3233-8.

Migraine can be induced by sildenafil without changes in middle cerebral artery diameter.

Migraine is considered a neurovascular disease involving dilatation of cerebral arteries. Nitric oxide (NO) donors induce dilatation of cerebral and extracranial arteries and migraine, but NO has several mechanisms of action in addition to its cyclic guanosine monophosphate (cGMP)-mediated vasodilatation. We examined whether sildenafil (Viagra), a selective inhibitor of cGMP-hydrolysing phosphodiesterase 5 (PDE5), which acts exclusively by increasing cGMP, can induce migraine and dilatation of cerebral arteries. We included 12 patients with migraine without aura in this double-blind, placebo-controlled crossover study, in which placebo or sildenafil 100 mg was administered orally on two separate days. Blood flow velocity in the middle cerebral artery (V(mca)) was recorded by transcranial Doppler ultrasonography and regional cerebral blood flow in the territory of the middle cerebral artery (rCBF(mca)) was measured using SPECT (single photon emission computed tomography) and xenon 133 inhalation. Radial and temporal artery diameters were studied using high-frequency ultrasonography. Headache response, tenderness of pericranial muscles, blood pressure and heart rate were measured repeatedly. We found that migraine attack was induced by sildenafil in 10 of 12 migraine patients and by placebo in two of 12 patients (P = 0.01). V(mca) (P = 0.1) and rCBF(mca) (P = 0.93) remained unchanged after sildenafil. Temporal (P = 0.47) and radial (P = 0.87) artery diameter and pericranial tenderness (P = 0.16) were unaffected by sildenafil. Systolic and diastolic blood pressures were unchanged but heart rate increased from a mean of 62 +/- 2 to 74 +/- 3 beats/min (P = 0.01) after sildenafil. Our results demonstrate that migraine may be induced via a cGMP-dependent mechanism, and we show for the first time that this occurs without initial dilatation of the middle cerebral artery. We propose that triggering mechanisms may reside within the perivascular sensory nerve terminals or the brainstem. However, other sites of action may also be possible and future studies are needed to elucidate this. In the clinical use of sildenafil, patients who have migraine should be informed about the risk of migraine attacks.

Brain. 2003 Jan;126(Pt 1):241-7

Erectile dysfunction severity as a risk marker for cardiovascular disease hospitalisation and all-cause mortality: a prospective cohort study.

BACKGROUND: Erectile dysfunction is an emerging risk marker for future cardiovascular disease (CVD) events; however, evidence on dose response and specific CVD outcomes is limited. This study investigates the relationship between severity of erectile dysfunction and specific CVD outcomes. METHODS AND FINDINGS: We conducted a prospective population-based Australian study (the 45 and Up Study) linking questionnaire data from 2006-2009 with hospitalisation and death data to 30 June and 31 Dec 2010 respectively for 95,038 men aged ≥45 y. Cox proportional hazards models were used to examine the relationship of reported severity of erectile dysfunction to all-cause mortality and first CVD-related hospitalisation since baseline in men with and without previous CVD, adjusting for age, smoking, alcohol consumption, marital status, income, education, physical activity, body mass index, diabetes, and hypertension and/or hypercholesterolaemia treatment. There were 7,855 incident admissions for CVD and 2,304 deaths during follow-up (mean time from recruitment, 2.2 y for CVD admission and 2.8 y for mortality). Risks of CVD and death increased steadily with severity of erectile dysfunction. Among men without previous CVD, those with severe versus no erectile dysfunction had significantly increased risks of ischaemic heart disease (adjusted relative risk [RR] = 1.60, 95% CI 1.31-1.95), heart failure (8.00, 2.64-24.2), peripheral vascular disease (1.92, 1.12-3.29), "other" CVD (1.26, 1.05-1.51), all CVD combined (1.35, 1.19-1.53), and all-cause mortality (1.93, 1.52-2.44). For men with previous CVD, corresponding RRs (95% CI) were 1.70 (1.46-1.98), 4.40 (2.64-7.33), 2.46 (1.63-3.70), 1.40 (1.21-1.63), 1.64 (1.48-1.81), and 2.37 (1.87-3.01), respectively. Among men without previous CVD, RRs of more specific CVDs increased significantly with severe versus no erectile dysfunction, including acute myocardial infarction (1.66, 1.22-2.26), atrioventricular and left bundle branch block (6.62, 1.86-23.56), and (peripheral) atherosclerosis (2.47, 1.18-5.15), with no significant difference in risk for conditions such as primary hypertension (0.61, 0.16-2.35) and intracerebral haemorrhage (0.78, 0.20-2.97). CONCLUSIONS: These findings give support for CVD risk assessment in men with erectile dysfunction who have not already undergone assessment. The utility of erectile dysfunction as a clinical risk prediction tool requires specific testing.

PLoS Med. 2013;10(1):e1001372.

Clinical assessment of a supplement of Pycnogenol® and L-arginine in Japanese patients with mild to moderate erectile dysfunction.

A double-blind parallel group comparison design clinical study was conducted in Japanese patients with mild to moderate erectile dysfunction to investigate the efficacy of a supplement containing Pycnogenol® and L-arginine. Subjects were instructed to take a supplement (Pycnogenol® 60 mg/day, L-arginine 690 mg/day and aspartic acid 552 mg/day) or an identical placebo for 8 weeks, and the results were assessed using the five-item erectile domain (IIEF-5) of the International Index of Erectile Function. Additionally, blood biochemistry, urinalysis and salivary testosterone were measured. Eight weeks of supplement intake improved the total score of the IIEF-5. In particular, a marked improvement was observed in 'hardness of erection' and 'satisfaction with sexual intercourse'. A decrease in blood pressure, aspartate transaminase and g-glutamyl transpeptidase (g-GTP), and a slight increase in salivary testosterone were observed in the supplement group. No adverse reactions were observed during the study period. In conclusion, Pycnogenol® in combination with L-arginine as a dietary supplement is effective and safe in Japanese patients with mild to moderate erectile dysfunction.

Phytother Res. 2012 Feb;26(2):204-7

Levels of l-arginine and l-citrulline in patients with erectile dysfunction of different etiology.

Nitric oxide is a physiologic signal essential to penile erection. l-citrulline (l-Cit) is converted into l-arginine (l-Arg), the precursor from which nitric oxide is generated. The level of l-Arg and l-Cit in the field of male sexual function remains relatively underexplored. The aim of the study was to evaluate the level of serum l-Arg and of l-Cit in a group of patients with erectile dysfunction. Diagnosis and severity of erectile dysfunction was based on the IIEF-5 and its etiology was classified as arteriogenic (A-ED), borderline (BL-ED), and non-arteriogenic (NA-ED) with penile echo-color-Doppler in basal condition and after intracaversous injection of prostaglandin E1. Serum l-Arg and l-Cit concentrations were measured by a cation-exchange chromatography system. l-Arg and l-Cit levels of men with A-ED were compared with those of male with BL-ED and NA-ED. Median level of l-Arg and l-Cit in 122 erectile dysfunction patients (41 A-ED, 23 ED-BL, 58 NA-ED) was 82.7 and 35.4 µmol/L, respectively. l-Arg and l-Cit levels in control patients were not significantly different (p = 0.233 and p = 0.561, respectively) than in total erectile dysfunction patients. l-Arg and l-Cit levels in control patients were significantly higher (p < 0.001 and p < 0.018, respectively) than in A-ED patients, but no difference (p > 0.50) was observed in controls and in both BL-ED and NA-ED patients. Patients with severe/complete-erectile dysfunction (IIEF-5 < 10) had l-Arg or l-Cit level significantly lower (-17%, p < 0.03; -13%, p < 0.04) and were more frequent (p < 0.01 and p < 0.04) under the respective median level (82.7 and 35.4 µmol/L) than those with mild-erectile dysfunction (IIEF-5 = 16-20). l-Arg and l-Cit levels in A-ED were significantly lower (p < 0.007 and p < 0.001, respectively) than in NA-ED patients. Penile echo-color-Doppler revealed that A-ED (peak systolic velocity ≤ 25 cm/sec) was more frequent in men with l-Arg under 82.7 µmol/L or l-Cit under 35.4 µmol/L and in the same population, the median peak systolic velocity values were lower in l-Arg deficient (29 vs. 35; p < 0.04) and also in l-Cit deficient (31 vs. 33, p > 0.3) but without reaching the statistical significance. Our study shows that a significant proportion of erectile dysfunction patients have low l-Arg or l-Cit level and that this condition is more frequent in patients with arteriogenic etiology. Low levels of these nitric oxide synthase substrates might increase the erectile dysfunction risk by reducing the concentration of nitric oxide.

Andrology. 2017 Mar;5(2):256-261

Skin care

The cosmetic treatment of wrinkles.

Wrinkles now have a greater social impact because people live longer. Science and hedonism overlap in the search for causes, treatments and prevention of wrinkles. The cosmetic approach to wrinkles includes: i Cleansing ii Photoprotection iii Active ingredients Active ingredients go well beyond simple moisturisers and exert a more complex activity in protecting skin from external injuries, nourishing it and removing its superficial layers. Transport systems and excipients are increasingly effective. Functional agents currently include alpha hydroxy acids (AHAs), poly-AHAs, complex poly-AHAs, retinoids, fish polysaccharides, anti-enzymatic agents, antioxidants (including ascorbic acid, pycnogenol, ursolic acid, vegetable isoflavones, vitamin E, coenzyme Q10, lipoic acid, resveratorol, l-carnosine and taurine) as well as agaricic acid and various plant extracts. All are reviewed in this text. Most are topical, some can be given by mouth, even as food supplements. Cosmetics are becoming closer to drugs in preventing and treating wrinkles. Included amongst the cosmeceuticals are the anti-wrinkle agents described herein.

J Cosmet Dermatol. 2004 Jan;3(1):26-34

The effect of a vitamin A palmitate and antioxidant-containing oil-based moisturizer on photodamaged skin of several body sites.

BACKGROUND: Cumulative lifetime sun exposure is accepted as having a very important role to play in the expression of the signs of photoaging, which is then superimposed on the intrinsic processes involved in th emulsion-based products, mostly although not exclusively, on the face using a variety of actives including retinoids and antioxidants. Nevertheless, the effect of a topical anhydrous product on photodamaged skin has not been reported in the literature. AIMS: The objective of this study was to clinically evaluate the effect of a vitamin A palmitate and antioxidant-containing oil-based moisturizer on facial, neck, decolletage, arms, and lower leg body sites. METHODS: In a randomized, controlled and efficacy grader-blinded clinical study conducted over 12 weeks, while at the same time recording the changes in skin condition for a no-treatment group over the same time period, live clinical expert grading of all body sites and also grading of photographs for the face and neck assessed changes in the signs of photodamage was performed for the treatment and no-treatment groups. RESULTS: Compared to the no-treatment group, and to baseline, the oil improved fine lines, coarse wrinkles, mottled pigmentation, uneven skin tone, roughness, firmness, and clarity of the skin on the face and neck and was also shown to improve crepey skin texture, dryness, scaling and roughness on the decolletage, arms and lower legs at the primary end point at 12 weeks (P < 0.001). Moreover, improvements in a variety of parameters were observed as quickly as 2 weeks. In general, the degree of improvement was greatest in the order legs > arms > decolletage > face > neck. CONCLUSIONS: Collectively, these results show the cumulative improvements in the signs of photoaging compared to a no-treatment control group for the oil-based antiaging moisturizer for the first time. The differences in the efficacy of the vitamin A palmiate and antioxidant oil-based moisturizer on different body sites probably reflect the differences in likely photodamage.

J Cosmet Dermatol. 2013 Mar;12(1):25-35

Penetration and metabolism of topical retinoids in ex vivo organ-cultured full-thickness human skin explants.

The human epidermis contains endogenous retinoids [retinol (vitamin A) and retinyl esters] and carotenoids (mostly beta-carotene). Previous studies in the mouse have shown that the enzymes involved in retinoid metabolism are present in the epidermis. In this study, we wanted to assess the skin penetration and metabolism of topical retinoids in the human. To do this, fresh surgically excised human abdominal skin was mounted on Franz perfusion cells. Topical retinoic acid, retinal, retinol and retinyl palmitate were applied at 2.5 mg/cm(2) in oil-in-water creams containing 0.05% retinoids on the donor compartment, while the receptor compartment was filled with culture medium. The skin was incubated for 24 h at 37 degrees C, then epidermal retinoid concentrations were determined by HPLC. The same experiment was performed with mouse back skin mounted on Franz cells. Finally, topical retinoids were applied on the back of hairless mice for 24 h; then the mice were sacrificed and retinoid concentrations were assayed in the epidermis. In all three models, retinol and its esters were found to be endogenous, as was the case in previous studies in the mouse in vivo. The four applied retinoids penetrated well into the epidermis. Topical retinoic acid did not increase endogenous retinoids, whereas the latter were greatly increased following topical retinal in the mouse. Retinal was also metabolized into retinoic acid, unlike topical retinol and retinyl palmitate, which only increased endogenous retinoids. Topical retinal and retinol did undergo a higher metabolism in both mouse models than in human skin. In summary, the penetration and metabolism patterns of topical retinoids were quite similar in the two mouse models used, indicating that the Franz cells appear to be a good model to predict in vivo metabolism of topical retinoids. When applying this concept to our results obtained in Franz cells with human skin, we conclude that topical retinol and retinal load human skin with both storage and functional vitamin A.

Skin Pharmacol Physiol. 2004 May-Jun;17(3):124-8

Age-related changes in skin barrier function - quantitative evaluation of 150 female subjects.

The protection against water loss and the prevention of substances and bacteria penetrating into the body rank as the most important functions of the skin. This so-called 'skin barrier function' is the natural frontier between the inner organism and the environment, and is primarily formed by the epidermis. An impairment of the skin barrier function is often found in diseased and damaged skin. An influence of ageing on skin barrier function is widely accepted, but has not been conclusively evaluated yet. Therefore, the aim of this clinical study was to assess the potential influence of ageing on skin barrier function, including transepidermal water loss (TEWL), stratum corneum hydration, sebum content and pH value. One hundred and fifty healthy women aged 18-80, divided into five age groups with 30 subjects each, were evaluated in this study. TEWL, hydration level, sebum secretion and pH value of hydro-lipid acid film were measured with worldwide acknowledged biophysical measuring methods at cheek, neck, décolleté, volar forearm and dorsum of hand. Whereas TEWL and stratum corneum hydration showed only very low correlation with subject's age, the sebum production decreased significantly with age, resulting in the lowest skin surface lipids levels measured in subjects older than 70 years. The highest skin surface pH was measured in subjects between 50 and 60 years, whereas the eldest age group had the lowest mean pH. The dorsum of the hand was the location with the highest TEWL and lowest stratum corneum hydration in all age groups. The results show that only some parameters related to skin barrier function are influenced by ageing. Whereas sebum production decreases significantly over lifetime and skin surface pH is significantly increased in menopausal woman, TEWL and stratum corneum hydration show only minor variations with ageing.

Int J Cosmet Sci. 2013 Apr;35(2):183-90

Effecting skin renewal: a multifaceted approach.

The skin undergoes intrinsic aging as a normal course, but exposure to ultraviolet (UV) light results in major cumulative damage that manifests as the typical aged photodamaged skin. UV irradiation produces a sequence of changes within the skin layers starting with signaling processes following DNA damage and culminating in nonabsorbed fragmentation of collagen and other proteins within the extracellular matrix. These fragments promote the synthesis of matrix metalloproteinases (MMPs) that further aggravate the damage to the ground substance and add to fragment accumulation. This study describes a unique sequential approach to controlling this photodamage - inhibition of signaling, inhibition of MMPs, proteasome stimulation and mopping up of fragments, stimulation of procollagen and collagen production, and uniform packaging of new collagen fibers. Thus, a multifaceted approach is introduced with presentation of a unique product formulation based on these research principles.

J Cosmet Dermatol. 2011 Jun;10(2):126-30

Anti-Aging Potential of Phytoextract Loaded-Pharmaceutical Creams for Human Skin Cell Longetivity.

The exposure to ultraviolet radiations (UVR) is the key source of skin sunburn; it may produce harmful entities, reactive oxygen species (ROS), leading to aging. The skin can be treated and protected from the injurious effects of ROS by using various pharmaceutical formulations, such as cream. Cream can be loaded with antioxidants to quench ROS leading to photo-protective effects. Moreover, modern medicines depend on ethnobotanicals for protection or treatment of human diseases. This review article summarizes various in vivo antioxidant studies on herbal creams loaded with phyto-extracts. These formulations may serve as cosmeceuticals to protect skin against injurious effects of UVR. The botanicals studied for dermatologic use in cream form include Acacia nilotica, Benincasa hispida, Calendula officinalis, Camellia sinensis, Camellia sinensis, Nelumbo nucifera, Capparis decidua, Castanea sativa, Coffea arabica, Crocus sativus, Emblica officinalis Gaertn, Foeniculum vulgare, Hippophae rhamnoides, Lithospermum erythrorhizon, Malus domestica, Matricaria chamomilla L., Moringa oleifera, Morus alba, Ocimum basilicum, Oryza sativa, Polygonum minus, Punica granatum, Silybum marianum, Tagetes erecta Linn., Terminalia chebula, Trigonella foenum-graecum, and Vitis vinifera. The observed anti-aging effects of cream formulations could be an outcome of a coordinating action of multiple constituents. Of numerous botanicals, the phenolic acids and flavonoids appear effective against UVR-induced damage; however the evidence-based studies for their anti-aging effects are still needed.

Oxid Med Cell Longev. 2015;2015:709628.

Heptapeptide-loaded solid lipid nanoparticles for cosmetic anti-aging applications.

The cosmetic industry requires more and more expensive actives and ingredients such as retinol, coenzyme Q10, proteins, peptides and biotechnologically produced molecules. In this study, we demonstrate the development of a cost effective formulation of a nanostructured lipid carrier (NLC) or solid lipid nanoparticles (SLN) improving peptide delivery into skin. NLC or SLN are very suitable vehicles for the delivery of active ingredients into skin. The SLN, produced by using hot high pressure homogenization method combine advantages such as physical stability, protection of incorporated labile actives and controlled release. By the used method we dispersed the amorphous heptapeptide DEETGEF in shea butter and homogenized this pre-dispersion at 60°C together with the water phase using a Microfluidizer at 1000bar. The analysis of the obtained SLN-P7 showed a particle size of 173nm, incorporated peptide of 0.014%, entrapment efficiency of 90.8%, melting peak (DSC) of the core lipid of 27°C and a zeta potential of -54mV. By an ex vivo study with skin explants we could stimulate NQO1 (NAD(P)H quinone oxidoreductase), HMOX1 (Heme oxygenase-1) and PRDX1 (Peroxiredoxin-1) genes all of which are cell protecting enzymes. In a multicellular protection against UV induced stress study with skin explants we detected the formation of sun burn cells and the number and morphology of Langerhans cells. The application of our SLN-P7 formulation on skin explants led to a significant and dose dependent protection against UV irradiation. In the clinical suction blister study, irradiation with UVA light for two hours after final product application led to a statistically significant increase of the 8-OhdG (8-hydroxy-2'-deoxyguanosine) concentration in the human epidermis. The skin treated with our verum formulation showed a statistically significant 20% decrease in DNA damage compared to placebo. In conclusion, it was demonstrated that SLN technology enabled peptide delivery into skin allowing it to perform protective functions

Eur J Pharm Biopharm. 2016 Nov;108:304-309

Blood sugar

Potent alpha-glucosidase inhibitors purified from the red alga Grateloupia elliptica.

Diabetes mellitus is a most serious and chronic disease whose incidence rates are increasing with incidences of obesity and aging of the general population over the world. One therapeutic approach for decreasing postprandial hyperglycemia is to retard absorption of glucose by inhibition of alpha-glucosidase. Two bromophenols, 2,4,6-tribromophenol and 2,4-dibromophenol, were purified from the red alga Grateloupia elliptica. IC(50) values of 2,4,6-tribromophenol and 2,4-dibromophenol were 60.3 and 110.4 microM against Saccharomyces cerevisiae alpha-glucosidase, and 130.3 and 230.3 microM against Bacillus stearothermophilus alpha-glucosidase, respectively. In addition, both mildly inhibited rat-intestinal sucrase (IC(50) of 4.2 and 3.6mM) and rat-intestinal maltase (IC(50) of 5.0 and 4.8mM). Therefore, bromophenols of G. elliptica have potential as natural nutraceuticals to prevent diabetes mellitus because of their high alpha-glucosidase inhibitory activity.

Phytochemistry. 2008 Nov;69(16):2820-5

Nutraceutical effects of fucoxanthin for obesity and diabetes therapy: a review.

Obesity, which results from an imbalance between energy intake and energy expenditure, has become a major health risk factor worldwide, causing numerous and various diseases such as diabetes, hypertension, and cardiovascular diseases. Fucoxanthin, a specific carotenoid in brown algae, has garnered much attention for its anti-obesity and anti-diabetic effects attributable to a unique mechanism. Fucoxanthin induces uncoupling protein 1 (UCP1) expression in white adipose tissue (WAT). That inner membrane mitochondrial protein, UCP1, can dissipate energy through oxidation of fatty acids and heat production. Furthermore, fucoxanthin improves insulin resistance and ameliorates blood glucose levels through down-regulation of adipocytokines related to insulin resistance in WAT and up-regulation of glucose transporter 4 (GLUT4) in skeletal muscle. Algae fucoxanthin is a beneficial compound for the prevention of the metabolic syndrome.

J Oleo Sci. 2015;64(2):125-32

Popular edible seaweed, Gelidium amansii prevents against diet-induced obesity.

The popular edible seaweed, Gelidium amansii is broadly used as food worldwide. To determine whether G. amansii extract (GAE) has protective effects on obesity, mice fed a high-fat diet (HFD) treated with GAE (1 and 3%) were studied. After 12 weeks of GAE treatment, body weight was greatly decreased in mice fed a high-fat diet. This effect could be due to decreased adipogenesis, as evidenced by the fact that GAE suppressed adipogenic gene expression in adipocytes. In addition, blood glucose and serum insulin levels were reduced by GAE treatment in mice fed a high-fat diet, suggesting improvement in glucose metabolism. GAE supplementation also led to a significant decrease in total cholesterol and triglyceride levels. These data are further confirmed by H&E staining. Our findings indicate that Gelidium amansii prevents against the development of diet-induced obesity, and further implicate that GAE supplementation could be the therapeutical option for treatment of metabolic disorder such as obesity.

Food Chem Toxicol. 2016 Apr;90:181-7

Anti-obesity effects of seaweeds of Jeju Island on the differentiation of 3T3-L1 preadipocytes and obese mice fed a high-fat diet.

The seaweeds were collected from the coast of Jeju Island, South Korea. We investigated ethanol extracts from seaweed as potential antiobesity agents by testing their effect on adipogenic differentiation in 3T3-L1 cells. Among the red algae extracts tested, the Plocamium telfairiae extract (PTE) showed the highest inhibitory effect on lipogenesis in adipocytes and, thus, was selected as a potential antiobesity agent. PTE treatment significantly decreased the expression of the adipogenic-specific proteins peroxisome proliferator-activated receptor-g, CCAAT/enhancer-binding protein-a, sterol regulatory element-binding protein 1, and fatty acid-binding protein 4 compared with that in the untreated 3T3-L1 cells. PTE also inhibited high-fat diet (HFD)-induced obesity in male C57BL/6 mice. Oral administration of PTE significantly reduced the body weight, fatty liver, amount of white adipose tissue, and levels of triglyceride and glucose in the tested animals. Taken together, these data demonstrate that PTE can be developed as a therapeutic agent for obesity.

Food Chem Toxicol. 2016 Apr;90:36-44

Compartmentalization and regulation of insulin signaling to GLUT4 by the cytoskeleton.

One of the early events in the development of Type 2 diabetes appears to be an inhibition of insulin-mediated GLUT4 redistribution to the cell surface in tissues that express GLUT4. Understanding this process, and how it begins to breakdown in the development of insulin resistance is quite important as we face treatment and prevention of metabolic diseases. Over the past few years, and increasing number of laboratories have produced compelling data to demonstrate a role for both the actin and microtubule networks in the regulation of insulin-mediated GLUT4 redistribution to the cell surface. In this review, we explore this process from insulin-signal transduction to fusion of GLUT4 membrane vesicles, focusing on studies that have implicated a role for the cytoskeleton. We see from this body of work that both the actin network and the microtubule cytoskeleton play roles as targets of insulin action and effectors of insulin signaling leading to changes in GLUT4 redistribution to the cell surface and insulin-mediated glucose uptake.

Vitam Horm. 2009;80:193-215

The molecular basis of insulin-stimulated glucose uptake: signalling, trafficking and potential drug targets.

The search for the underlying mechanism through which insulin regulates glucose uptake into peripheral tissues has unveiled a highly intricate network of molecules that function in concert to elicit the redistribution or 'translocation' of the glucose transporter isoform GLUT4 from intracellular membranes to the cell surface. Following recent technological advances within this field, this review aims to bring together the key molecular players that are thought to be involved in GLUT4 translocation and will attempt to address the spatial relationship between the signalling and trafficking components of this event. We will also explore the degree to which components of the insulin signalling and GLUT4 trafficking machinery may serve as potential targets for the development of orally available insulin mimics for the treatment of diabetes mellitus.

J Endocrinol. 2009 Oct;203(1):1-18

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