Male sexual dysfunction: A review of literature on its pathological mechanisms, potential risk factors, and herbal drug intervention.

Sexual dysfunction (SD) is a disorder of sexual behavior and sexual sensation that appears as an abnormality or absence of sexual psychology and physiological reaction. It is a general term for many different symptoms includes several aspects, erectile dysfunction (ED), failure of sexual intercourse and loss of libido/desire. According to statistics, 52% of 40˜70 year old men suffer from varying degrees of SD. And these diseases caused by a variety of biological and psychological factors. In world about 15% of couples are affected by sexual disharmony among these 40 to 50% are because of male factors. Considering the sensitivity of male reproduction system, it is being easily affected by multiple risk factors, such as chronic diseases, environmental contaminants, drug toxicity and unhealthy lifestyle and so on. In the last few years, significant progress have been made toward understanding the various forms of male SD and the possible potential pathological mechanisms. However, for the time being, the exact cause of SD is not fully understood from the literature. What is also significant about there are quite limited treatments in reproductive medicine being directed against these lesions. The purpose of this review is to summarize the current findings of pathogenic factors of SD in clinical or animal studies, to elaborate the underlying mechanisms of these diseases from studies in vivo and in vitro, to analyses the risk factors, and to describe the management strategies traditionally recommended of male sexual dysfunction. The review findings elucidate a systematic strategies for effectively preventing these diseases.

In vitro and in vivo evidence that quercetin protects against diabetes and its complications: A systematic review of the literature.

Quercetin, a typical flavonoid, possesses diverse biochemical and physiological actions, including antiplatelet, estrogenic, and anti-inflammatory properties. This review mainly centers on recent ten years findings with respect to intervening diabetes and its complications with the well-known flavonoid quercetin. After a short introduction of quercetin, major in vitro and in vivo findings are summarized showing that quercetin is a promising molecule for the treatment of these diseases. Finally, we contemplate future development and application prospects of quercetin. Despite the wealth of in animal research results suggesting the anti-diabetic and its complications potential of quercetin, its efficacy in diabetic human subjects is yet to be explored. The problem may become an important direction in the future research.

Lycium barbarum polysaccharide attenuates diabetic testicular dysfunction via inhibition of the PI3K/Akt pathway-mediated abnormal autophagy in male mice.

Testicular dysfunction is one of the serious secondary complications in diabetes. Lycium barbarum polysaccharide (LBP) has long been considered to possess a wide range of beneficial properties including antiaging, anticancer and reproductive-enhancing. Abnormal autophagy was reported to play a significant role in accelerating diabetic reproductive injury. However, the autophagy regulation mechanism of LBP on diabetic testicular dysfunction is incompletely understood. We investigate the protective effects of LBP on diabetic testicular dysfunction and its underlying mechanism with different approaches. Protective effects of LBP (40 mg/kg) on testicular functions were assessed through the use of sperm parameters, testosterone levels and hematoxylin and eosin staining. Antioxidant capacity and serum malondialdehyde levels were determined using assay kits. Immune intensity of Beclin-1 and LC3I in testes was detected by immunofluorescence staining. Western blot analysis was used to detect expressions of p-PI3K, Akt, p-Akt, Beclin-1, LC3I and LC3II proteins. Q-PCR was used to evaluate Beclin-1 and LC3I mRNA expressions in testis. Administration of LBP (40 mg/kg) considerably recovered testicular function, obviously improved testicular histopathologic structure and significantly increased antioxidant enzyme activities. Immunofluorescence staining showed that immune intensity of Beclin-1 and LC3I significantly decreased in the LBP 40 mg/kg group. The results of Q-PCR and western blot analysis showed that LBP 40 mg/kg significantly downregulated Beclin-1 and LC3I protein expressions upregulated p-PI3K and p-Akt protein expressions and decreased Beclin-1 and LC3I mRNA expressions compared with diabetic mice. In conclusion, inhibition of PI3K/Akt pathway-mediated testicular excessive autophagy may be a target for protective effects of LBP on diabetic testicular dysfunction.

Involvement of growth factors in diabetes mellitus and its complications: A general review.

Diabetes mellitus (DM) is a major endocrine metabolic disease and is marked by a lack of insulin. The complication of DM is one of the most difficult problems in medicine. The initial translational studies revealed that growth factors have a major role in integrating tissue physiology and in embryology as well as in growth, maturation and tissue repair. In some tissues affected by diabetes, growth factors are induced by a relative deficit or excess. Fibroblast growth factor 21 (FGF21) is a promising regulator of glucose and lipid metabolism with multiple beneficial effects including hypoglycemic and lipid-lowering. Vascular endothelial growth factor (VEGF) is a potent angiogenic and vascular permeability factor and is implicated in both of these complications in diabetes. Increase or decrease in the production of transforming growth factor-ß1 (TGF-ß1) has been associated with diabetic nephropathy and retinopathy. The insulin-like growth factor-I (IGF-I) is a naturally-occurring single chain polypeptide which has been widely used in the treatment of diabetic glomerular and renal tubular injuries. This review summarizes the recent evidences for an involvement of growth factors in diabetic complications, focusing on their emergence in sequence of events leading to vascular complications or their potential therapeutic role in these diseases. Growth factor therapy in diabetic foot ulcers is already a clinical reality. As methods to finely regulate growth factors in a tissue and time-specific manner are further developed and tested, regulation of the growth factor to normal level in vivo may well become a therapy to prevent and treat diabetic complications.

Protective effects of Lycium barbarum polysaccharide on male sexual dysfunction and fertility impairments by activating hypothalamic pituitary gonadal axis in streptozotocin-induced type-1 diabetic male mice.

Diabetes-associated male sexual dysfunction and fertility impairments are both common clinical complications with limited therapeutic options; hence it seriously affects the quality of life of the patients, in particular, the patients of reproductive age. Lycium barbarum polysaccharide (LBP) has long being believed to maintain and to promote reproductive functions in the traditional medical practice in China. The current study was to investigate if LBP may contribute to recovery of male sexual dysfunction and fertility impairments in diabetic individuals. The effects of LBP on sexual behaviors and histological changes of testis were studied in the type-1 diabetes male mice induced by intra-peritoneal (i.p.) injection of streptozotocin (STZ). After oral administration of LBP (10, 20 or 40 mg/kg), sildenafil citrate (SC, 5 mg/kg) or saline for 62 consecutive days, the typical abnormal changes in the sperm parameters, in relative weight of reproductive organs and in morphology of testis were observed in diabetic mice. LBP treatment of the diabetic mice considerably reversed those changes and Johnsen's testicular score, serum testosterone (T), follicular stimulating hormone (FSH) and luteinizing hormone (LH) level were also increased to different degrees. Moreover, our data have also shown that a marked improvement in sexual behavior and fertility level after administration of LBP (40 mg/kg) compared to the diabetic group. These results suggested that LBP can exert functional recovery of male sexual dysfunction and fertility damages induced by diabetes in male mice, which is likely to be mediated through regulating the hypothalamus- pituitary-gonadal axis endocrine activity.

Diabetes associated with male reproductive system damages: Onset of presentation, pathophysiological mechanisms and drug intervention.

Diabetes mellitus (DM) is a major health problem that affects patients' quality of life quality throughout the world due to its many complications. Reproductive dysfunction is one of the major secondary complications in both diabetic animals and human beings. Furthermore, DM has recently broken the age barrier and has been heavily diagnosed in children and young persons of reproductive age. In the past few years, many studies on DM in male reproductive functions in both diabetic men and experimental diabetic animals have been published. It is recognized that sustained hyperglycemia, which impairs reproductive function in diabetic men, is at risk of developing. DM harmfully affects male reproductive functions in multiple areas; these may include spermatogenesis, sperm maturation, fertility capability, penile erection, and ejaculation. Traditional medicine and folklore worldwide have used numerous medicinal plants to manage the diabetic reproductive dysfunction because bioactive phyto-constituents are affluent in many places. Unfortunately, the exact reasons for diabetic male reproductive dysfunction are not completely understood and currently there are no treatments in reproductive medicine specifically for such lesions. The aim of this review is to summarize current research findings of DM on reproductive functions, to elaborate the underlying mechanisms related to these diseases via in vivo and in vitro studies, and to describe the ameliorative effects of medicinal plants or their products. The review findings provide a systematic understanding of DM on the reproductive functions and lay the theoretical foundation for developing the direction of reproductive medicine.

Beneficial effects of Lycium barbarum polysaccharide on spermatogenesis by improving antioxidant activity and inhibiting apoptosis in streptozotocin-induced diabetic male mice.

Spermatogenic dysfunction is one of the major secondary complications of diabetes. L. barbarum polysaccharide (LBP) has long been considered to possess anti-apoptotic activities and antioxidant, anti-inflammatory and fertility-enhancing properties in traditional medical practices in China. The aim of the current study was to seek out scientific evidence to determine if LBP also contributes to the recovery from spermatogenic dysfunction in diabetic individuals. We investigated whether the oral administration of LBP in streptozotocin (STZ)-induced type-1 diabetic male mice would reverse spermatogenic dysfunction and improve histological damage in testes. After the oral administration of LBP (10, 20 or 40 mg kg-1, respectively), sildenafil citrate (5 mg kg-1) or saline for 62 consecutive days, the sperm parameters were analyzed. Macroscopic and microscopic changes in the reproductive organs, including their weight, and photomicroscope and electronmicroscope images were also assessed. In addition, the antioxidant capacity and levels of malondialdehyde in the testes were determined according to the instructions provided with the assay kits and the expression of the apoptosis-related proteins, Caspase-3, Bax and Bcl-2, in the testes was analyzed using western-blot analysis. LBP treatment of diabetic mice considerably recovered the sperm parameters, increased the weight of the reproductive organs, ameliorated their histological appearance and increased antioxidant enzyme activity to different degrees. Moreover, our data also showed a marked decrease in Caspase-3 expression and an increase in the ratio of Bcl-2/Bax 43 after LBP administration (40 mg kg-1) when compared to the diabetic group. These results demonstrate that LBP exerts protective effects on diabetes induced male spermatogenic dysfunction, which is likely to be mediated through increasing antioxidant enzyme activities and inhibiting cell death.

Observing Anti-inflammatory and Anti-nociceptive Activities of Glycyrrhizin Through Regulating COX-2 and Pro-inflammatory Cytokines Expressions in Mice.

The present study aimed to investigate the potential anti-inflammatory and anti-nociceptive activities of glycyrrhizin (GL) in mice and to explore the possible related mechanisms. Xylene-induced ear edema, carrageenan-induced paw edema and acetic acid-induced vascular permeability test were used to investigate the anti-inflammatory activities of GL in mice. Anti-nociceptive effects of GL were assessed by using acetic acid-induced writhing, hot plate test and formalin test, as well as evaluation of spontaneous locomotor activity and motor performance. The mRNA expression of pro-inflammatory cytokines (such as TNF-α, IL-6 and iNOS) and the protein expression of cyclooxygenase-2 (COX-2) were explored by using real-time fluorogenic PCR and Western blot, respectively. The results showed that GL significantly reduced xylene-induced ear edema, carrageenan-induced paw edema, and acetic acid-induced vascular permeation. Additionally, GL significantly inhibited the nociceptions induced by acetic acid and formalin. However, the nociceptions could not be decreased by GL in the hot plate test, and GL did not affect spontaneous locomotor activity and motor performance. The expression levels of TNF-α, IL-6, iNOS and COX-2 were significantly downregulated by GL. In conclusion, GL exerts significant anti-inflammatory and analgesic activities by attenuating the expression levels of TNF-α, IL-6, iNOS and COX-2.