Antioxidative mechanism of Lycium barbarum polysaccharides promotes repair and regeneration following cavernous nerve injury

Argonaute 2 restored erectile function and corpus cavernosum mitochondrial function by reducing apoptosis in a mouse model of cavernous nerve injury

PURPOSE

To determine whether the overexpression of the Argonaute RNA-induced silencing complex catalytic component 2 (Ago2) improves erectile function in mice after cavernous nerve injury (CNI).

MATERIALS AND METHODS

Lentiviruses containing Ago2 open reading frame (ORF) mouse clone (Ago2 O/E) were used to overexpress Ago2, and lentiviruses ORF negative control particles (NC) were used as a negative control. Three days before preparing the CNI model, we injected lentiviruses into the penises of 8-week-old male C57BL/6 mice. Animals were then divided into four groups: the sham operation control group and the CNI+phosphate-buffered saline, CNI+NC, and CNI+Ago2 O/E groups. One week later, erectile function was assessed by electrically stimulating cavernous nerves bilaterally and obtaining intracavernous pressure parameters. Penile tissue was also collected for molecular mechanism studies.

RESULTS

Ago2 overexpression improved erectile function in mice after CNI-induced erectile dysfunction (ED). Immunofluorescence staining and Western blot analysis showed that under Ago2 overexpressing conditions, the contents of endothelial cells, pericytes, and neuronal cells increased in the penile tissues of CNI mice, and this was attributed to reduced apoptosis and ROS production. In addition, we also found that Ago2 overexpression could restore penile mitochondrial function, thereby improving erectile function in CNI-induced ED mice.

CONCLUSIONS

Our findings demonstrate that Ago2 overexpression can reduce penile cell apoptosis, restore penile mitochondrial function, and improve erectile function in CNI-induced ED mice.

Updated Progress on Polysaccharides with Anti-Diabetic Effects through the Regulation of Gut Microbiota: Sources, Mechanisms, and Structure-Activity Relationships

Diabetes mellitus (DM) is a common chronic metabolic disease worldwide. The disturbance of the gut microbiota has a complex influence on the development of DM. Polysaccharides are one type of the most important natural components with anti-diabetic effects. Gut microbiota can participate in the fermentation of polysaccharides, and through this, polysaccharides regulate the gut microbiota and improve DM. This review begins by a summary of the sources, anti-diabetic effects and the gut microbiota regulation functions of natural polysaccharides. Then, the mechanisms of polysaccharides in regulating the gut microbiota to exert anti-diabetic effects and the structure-activity relationship are summarized. It is found that polysaccharides from plants, fungi, and marine organisms show great hypoglycemic activities and the gut microbiota regulation functions. The mechanisms mainly include repairing the gut burrier, reshaping gut microbiota composition, changing the metabolites, regulating anti-inflammatory activity and immune function, and regulating the signal pathways. Structural characteristics of polysaccharides, such as monosaccharide composition, molecular weight, and type of glycosidic linkage, show great influence on the anti-diabetic activity of polysaccharides. This review provides a reference for the exploration and development of the anti-diabetic effects of polysaccharides.

Dimethyl fumarate ameliorates erectile dysfunction in bilateral cavernous nerve injury rats by inhibiting oxidative stress and NLRP3 inflammasome-mediated pyroptosis of nerve via activation of Nrf2/HO-1 signaling pathway

OBJECTIVE

To investigate the therapeutic potential of dimethyl fumarate (DMF) in improving erectile function of bilateral cavernous nerve injury (BCNI) rats, along with elucidating its underlying mechanisms.

METHODS

A BCNI rat model was established by clamping bilateral cavernous nerve (CN). DMF was given by gavage at low (20 mg/kg/day) and high (40 mg/kg/day) dosages for a duration of 4 weeks. Erectile function was assessed by electrical stimulation of CN. Penis and CN tissues were collected for subsequent analysis. Additionally, PC-12 cell line was used to verify the mechanism of DMF in vitro. Nfe2l2 or Ho-1 gene knockdown PC-12 cell lines were constructed by lentiviral transfection, respectively. A damaged cell model was induced using H2O2. And then molecular biological methods were employed to analyze cellular molecules and proteins.

RESULTS

DMF administration for 4 weeks led to improvements in erectile function, reduced fibrosis of penis corpus cavernosum in BCNI rats. The morphology of CN was improved and the number of nerve fibers increased. Furthermore, the levels of nNOS, NO, and cGMP were increased, while Ca2+ was decreased in penis corpus cavernosum. Notably, the levels of ROS, 3-NT and NLRP3 inflammasomes production were reduced, alongside increased expression of Nrf2 and HO-1 proteins in the dorsal penile nerve (DPN) and CN. In vitro, DMF increased cell viability, reduced ROS level, promoted SOD, diminished 3-NT, MDA and DNA damage markers, and inhibited the activation of NLRP3 inflammasomes in H2O2 induced PC-12 cells. Nfe2l2 knockdown and Ho-1 knockdown significantly attenuated the protective effect of DMF, respectively. Furthermore, inhibition of ROS production by N-acetylcysteine led to a reduction in NLRP3 inflammasome activation in H2O2 induced PC-12 cells.

CONCLUSIONS

DMF improved erectile function of BCNI rats by protecting nerves through inhibiting oxidative stress and the activation of NLRP3 inflammasome-mediated pyroptosis via activation of Nrf2/HO-1 pathway.

Lycium barbarum glycopeptide alleviates neuroinflammation in spinal cord injury via modulating docosahexaenoic acid to inhibiting MAPKs/NF-kB and pyroptosis pathways

BACKGROUND

Lycium barbarum polysaccharide (LBP) is an active ingredient extracted from Lycium barbarum that inhibits neuroinflammation, and Lycium barbarum glycopeptide (LbGp) is a glycoprotein with immunological activity that was purified and isolated from LBP. Previous studies have shown that LbGp can regulate the immune microenvironment, but its specific mechanism of action remains unclear.

AIMS

In this study, we aimed to explore the mechanism of action of LbGp in the treatment of spinal cord injury through metabolomics and molecular experiments.

METHODS

SD male rats were randomly assigned to three experimental groups, and after establishing the spinal cord hemisection model, LbGp was administered orally. Spinal cord tissue was sampled on the seventh day after surgery for molecular and metabolomic experiments. In vitro, LbGp was administered to mimic the inflammatory microenvironment by activating microglia, and its mechanism of action in suppressing neuroinflammation was further elaborated using metabolomics and molecular biology techniques such as western blotting and q-PCR.

RESULTS

In vivo and in vitro experiments found that LbGp can improve the inflammatory microenvironment by inhibiting the NF-kB and pyroptosis pathways. Furthermore, LbGp induced the secretion of docosahexaenoic acid (DHA) by microglia, and DHA inhibited neuroinflammation through the MAPK/NF-κB and pyroptosis pathways.

CONCLUSIONS

In summary, we hypothesize that LbGp improves the inflammatory microenvironment by regulating the secretion of DHA by microglia and thereby inhibiting the MAPK/NF-κB and pyroptosis pathways and promoting nerve repair and motor function recovery. This study provides a new direction for the treatment of spinal cord injury and elucidates the potential mechanism of action of LbGp.

Buyang Huanwu Decoction Ameliorates Damage of Erectile Tissue and Function Following Bilateral Cavernous Nerve Injury

OBJECTIVE

To verify the effect of Buyang Huanwu Decoction (BHD) in ameliorating erectile dysfunction (ED) after radical prostatectomy (RP).

METHODS

The composition of BHD was verified by ultra-performance liquid chromatography quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS/MS) analysis. Bilateral cavernous nerve crush injury (BCNI) in rats was used to mimic the neurovascular injury occurring after RP. By the envelope method, forty rats were randomly divided into 4 groups as follows: sham (cavernous nerves exposed only), model (BCNI), low-dosage BHD [LBHD, 12.8 g/(kg·d)], and high-dosage BHD [HBHD, 51.2 g/(kg·d)] groups, 10 rats in each group, feeding for 3 weeks respectively. Erectile function was evaluated by measuring intracavernosal pressure (ICP). Changes in the histopathology of corpus cavernosum (CC) were examined by hematoxylin-eosin staining. Meanwhile, the fibrosis of CC was measured by Masson's trichrome staining and Western blot was used to detect the expressions of collagen I, transforming growth factor beta 1 (TGF- β 1) and α-smooth muscle actin (α-SMA). Apoptosis index was detected by terminal-deoxynucleoitidyl transferase mediated nick end labeling (TUNEL) and Western blot for determining the expressions of B-cell lymphoma 2 (Bcl-2) and Bcl-2-associated X (Bax). The oxidative stress in the CC were assessed by the superoxide dismutase (SOD), malondialdehyde (MDA) and reactive oxygen species (ROS) levels. The proteins expression of c-Jun N-terminal kinase (JNK) and c-Jun were detected by Western blot. In addition, the expression of α-SMA and p-c-Jun in the CC was observed by double immunofluorescence staining.

RESULTS

The UPLC-QTOF-MS/MS analysis showed that BHD contained calycosin-7-O- β -D-glucoside, ononin, calycosin and formononetin. Compared with the model group, LBHD and HBHD treatment improved the ICP and the circumference, area, and weight of CC (P<0.05 or P<0.01). Furthermore, LBHD and HBHD treatments increased CC smooth muscle content and decreased apoptosis index (P<0.05 or P<0.01). LBHD and HBHD also elevated SOD and expression level of α -SMA and Bcl-2, and reduced MDA and ROS levels, as well as expression of TGF- β 1, collagen I, Bax, p-c-JNK, p-JNK in the CC compared with the model group (P<0.05 or P<0.01). The double immunofluorescence staining showed that the fluorescence degree of p-c-Jun in both LBHD and HBHD treatment groups was significantly reduced, whereas the α -SMA expression increased (P<0.05 or P<0.01).

CONCLUSIONS

BHD can improve ED of rats with BCNI, which is related to inhibiting fibrosis, apoptosis, and oxidative stress of CC. The ROS/JNK/c-Jun signaling pathway may play an important role in the process.

Distinct Role of Lycium barbarum L. Polysaccharides in Oxidative Stress-Related Ocular Diseases

Oxidative stress is an imbalance between the increased production of reactive species and reduced antioxidant activity, which can cause a variety of disturbances including ocular diseases. Lycium barbarum polysaccharides (LBPs) are complex polysaccharides isolated from the fruit of L. barbarum, showing distinct roles in antioxidants. Moreover, it is relatively safe and non-toxic. In recent years, the antioxidant activities of LBPs have attracted remarkable attention. In order to illustrate its significance and underlying therapeutic value for vision, we comprehensively review the recent progress on the antioxidant mechanisms of LBP and its potential applications in ocular diseases, including diabetic retinopathy, hypertensive neuroretinopathy, age-related macular degeneration, retinitis pigmentosa, retinal ischemia/reperfusion injury, glaucoma, dry eye syndrome, and diabetic cataract.

Comparison of the therapeutic effects of human umbilical cord blood-derived mesenchymal stem cells and adipose-derived stem cells on erectile dysfunction in a rat model of bilateral cavernous nerve injury

Background: Cavernous nerve injury (CNI) is the leading cause of erectile dysfunction (ED) after radical prostatectomy and pelvic fracture. Transplantation of human adipose-derived stem cells (ASCs) has been widely used to restore erectile function in CNI-ED rats and patients. Umbilical cord blood-derived MSCs (CBMSCs) are similarly low immunogenic but much primitive compared to ASCs and more promising in large-scale commercial applications due to the extensive establishment of cord blood banks. However, whether CBMSCs and ASCs have differential therapeutic efficacy on CNI-ED and the underlying mechanisms are still not clear.

Materials and methods: A bilateral cavernous nerve injury (BCNI) rat model was established by crushing the bilateral cavernous nerves. After crushing, ASCs and CBMSCs were intracavernously injected immediately. Erectile function, Masson staining, and immunofluorescence analyses of penile tissues were assessed at 4 and 12 weeks. PKH-26-labeled ASCs or CBMSCs were intracavernously injected to determine the presence and differentiation of ASCs or CBMSCs in the penis 3 days after injection. In vitro experiments including intracellular ROS detection, mitochondrial membrane potential assay, EdU cell proliferation staining, cell apoptosis assay, and protein chip assay were conducted to explore the underlying mechanism of CBMSC treatment compared with ASC treatment.

Results: CBMSC injection significantly restored erectile function, rescued the loss of cavernous corporal smooth muscles, and increased the ratio of smooth muscle to collagen. PKH-26-labeled CBMSCs or ASCs did not colocalize with endothelial cells or smooth muscle cells in the corpus cavernosum. Moreover, the conditioned medium (CM) of CBMSCs could significantly inhibit the oxidative stress and elevate the mitochondria membrane potential and proliferation of Schwann cells. Better therapeutic effects were observed in the CBMSC group than the ASC group both in vivo and in vitro. In addition, the content of neurotrophic factors and matrix metalloproteinases in CBMSC-CM, especially NT4, VEGF, MMP1, and MMP3 was significantly higher than that of ASC-CM.

Conclusion: Intracavernous injection of CBMSCs exhibited a better erectile function restoration than that of ASCs in CNI-ED rats owing to richer secretory factors, which can promote nerve regeneration and reduce extracellular matrix deposition. CBMSC transplantation would be a promising therapeutic strategy for CNI-ED regeneration in the future.

Molecular pathogenesis and treatment of cavernous nerve injury-induced erectile dysfunction: A narrative review

Introduction: Erectile dysfunction (ED) is a common complication after radical prostatectomy (RP), and it seriously affects the quality of life in patients and their partners. The primary trigger of postoperative ED is surgical injury to the cavernous nerves that control penile erection and run along the anterolateral aspect of the prostate. Despite the introduction and ongoing innovation of nerve-sparing techniques, a significant number of patients still suffer from moderate cavernous nerve injury (CNI), which is thought to be transient and reversible. Therefore, early postoperative penile rehabilitation therapy may salvage patients’ erectile function by promoting cavernous nerve regeneration and preventing penile structural alterations.

Aims: To present a comprehensive overview of the current molecular pathogenesis of CNI-induced ED, as well as novel therapeutic strategies and their potential mechanisms.

Methods: A literature search was performed using PubMed. Search terms included erectile dysfunction, cavernous nerve injury, pathogenesis, pathway, and treatment.

Results: The NOS/NO pathway, oxidative stress-related pathway, RhoA/ROCK pathway, transforming growth factor-β (TGF-β), sonic hedgehog (Shh), and hydrogen sulfide (H2S) are involved in the molecular pathogenesis of CNI-induced ED. Multiple neurotrophins, including brain-derived nerve growth factor (BDNF), glial cell line-derived neurotrophic factor (GDNF), and neurturin (NTN), were found to promote cavernous nerve regeneration. Emerging therapeutic approaches can be roughly summarized into four categories, namely small molecule and drug, stem cell-based therapy (SCT), micro-energy therapy and platelet-rich plasma (PRP) therapy.

Conclusion: These pathways collectively lead to the irreversible damage to the penile structure after CNI. The combined early rehabilitation strategies of promoting upstream nerve regeneration and recovering abnormal molecular signals of downstream penis are presumed to save patients’ erectile function after RP. In future studies, the cross-talk between these molecular pathways needs to be further clarified, and the questions of how denervation injury induces the molecular alterations in the penis also need to be addressed.

An update on the current status and future prospects of erectile dysfunction following radical prostatectomy

BACKGROUND

Radical prostatectomy (RP) and radiation treatment are standard options for localized prostate cancer. Even though nerve-sparing techniques have been increasingly utilized in RP, erectile dysfunction (ED) due to neuropraxia remains a frequent complication. Erectile function recovery rates after RP remain unsatisfactory, and many men still suffer despite the availability of various therapies.

OBJECTIVE

This systematic review aims to summarize the current treatments for post-RP-ED, assess the underlying pathological mechanisms, and emphasize promising therapeutic strategies based on the evidence from basic research.

METHOD

Evaluation and review of articles on the relevant topic published between 2010 and 2021, which are indexed and listed in the PubMed database.

RESULTS

Phosphodiesterase type 5 inhibitors, intracavernosal and intraurethral injections, vacuum erection devices, pelvic muscle training, and surgical procedures are utilized for penile rehabilitation. Clinical trials evaluating the efficacy of erectogenic drugs in this setting are conflicting and far from being conclusive. The use of androgen deprivation therapy in certain scenarios after RP further exacerbates the already problematic situation and emphasizes the need for effective treatment strategies.

CONCLUSION

This article is a detailed overview focusing on the pathophysiology and mechanism of the nerve injury developed during RP and a compilation of various strategies to induce cavernous nerve regeneration to improve erectile function (EF). These strategies include stem cell therapy, gene therapy, growth factors, low-intensity extracorporeal shockwave therapy, immunophilins, and various pharmacological approaches that have induced improvements in EF in experimental models of cavernous nerve injury. Many of the mentioned strategies can improve EF following RP if transformed into clinically applicable safe, and effective techniques with reproducible outcomes.

Lycium barbarum Polysaccharides as Antibiotic Substitutes Improve Growth Performance, Serum Immunity, Antioxidant Status, and Intestinal Health for Weaned Piglets

The aim of the present study is to investigate the effects of dietary Lycium barbarum polysaccharides (LBPs) supplementation on the growth performance, immune response, serum antioxidant status, and intestinal health of weaned piglets. In total, 24 crossed healthy weaned piglets [Duroc × (Yorkshire × Landrace)], of similar body weight (7.47 ± 0.22 kg), were randomly allocated to three treatment groups: CON (basal diet); LBPs (basal diet plus 4,000 mg/kg LBPs); and antibiotic (ABO, basal diet plus 20 mg/kg flavomycin and 50 mg/kg quinocetone). There were eight pigs per group. The study lasted 28 days. When compared with CON, LBPs or ABO dietary supplementation increased average daily gain (P < 0.05), decreased the ratio of feed to gain and the diarrhea ratio (P < 0.05). Similarly, when compared with CON, LBPs dietary supplementation increased serum immunoglobulin G, immunoglobulin M, interleukin-10, interleukin-2, and tumor necrosis factor-α levels (P < 0.05). Dietary LBPs enhanced the activity of serum total antioxidant capacity and glutathione peroxidase, and decreased malondialdehyde levels (P < 0.05). Principal component analysis showed a distinct separation between CON and LBPs groups, but no differences between ABO and LBPs groups. LBPs addition increased Lactobacillus and Faecalibacterium (P < 0.05) levels, while it decreased Enterococcaceae and Enterobacteriaceae (P < 0.05) levels. Furthermore, when compared with the CON group, LBPs increased villus height (P < 0.05) and the villus height to crypt depth ratio in the duodenum and jejunum (P < 0.05). Thus, dietary supplementation with LBPs improved growth performance, antioxidant capacity and immunity, regulated intestinal microbial composition, and may be used as an efficient antibiotic alternative in weaned piglet feed.

Bioaccessibility and antioxidant activity of β-carotene loaded nanostructured lipid carrier (NLC) from binary mixtures of palm stearin and palm olein

β-carotene (βC) is an essential nutrient for health. It is a potent antioxidant, anti-cancer, and anti-inflammatory substance. However, βC has high hydrophobicity property, indicating a low absorption level in the digestive tract. The bioavailability of βC is reasonably low. Lipid-based delivery systems such as nanostructured lipid carriers (NLC) potentially can help to overcome this problem. This research evaluated the bioaccessibility of the nanostructured mixture of palm stearin (PS) and palm olein (PO) and the antioxidant activity of βC in the structure. β-carotene bioaccessibility was studied by measuring the micellization during in vitro digestion. Antioxidants activity was measured by 2.2′-azino-bis (3-ethylbenzothiazoline- 6-sulphonic acid) (ABTS) and 2, 2 – diphenyl -1- picrylhydrazyl (DPPH) reduction methods. In vitro gastrointestinal digestion model indicated that nanostructured lipid carrier enhanced bioaccessibility and antioxidants activity of βC. This suggests that the formulated NLC system can be used effectively to deliver lipophilic bioactive such as βC in beverage products.

Ziziphus jujube ameliorated cavernosal oxidative stress and fibrotic processes in cavernous nerve injury-induced erectile dysfunction in a rat model

The aim of this study was to investigate potential antioxidant and antifibrotic effects of Ziziphus jujube (ZJ) in a cavernosal nerve injury (CNI)-induced erectile dysfunction (ED) rat model. Forty-eight male rats were assigned to six-sized groups as group 1: sham-operated; group 2: sham-operated + low-dose ZJ (200 mg/kg); group 3: sham-operated + high-dose ZJ (400 mg/kg); group 4: CNI + distilled water; group 5: CNI + low-dose ZJ; and group 6: CNI + high-dose ZJ. At the end of 2 weeks, intracardiac blood was taken and rats were sacrificed. For biochemical analysis, cavernosal transforming growth factor-beta-1, collagen type I and type 3, fibronectin, α and β actin were examined in plasma and cavernosa. Superoxide dismutase (SOD), catalase (CAT), malondialdehyde (MDA) and prolidase levels were measured in serum to evaluate antioxidant effect of ZJ. Histopathological examination of tissues revealed that highest fibrosis rate was in group 4 (66.84%). Collagen 1 and 3, alpha and beta actin, fibronectin levels were significantly different among groups (p < .05). Differences between plasma SOD, CAT, MDA and prolidase were also significant among those groups (p < .05). In this study, antioxidant and antifibrotic effects of ZJ were determined in the corporal tissue after CNI. It is thought that ZJ may be beneficial on ED patients especially after radical pelvic surgeries.

Reparative effects of lycium barbarum polysaccharide on mouse ovarian injuries induced by repeated superovulation

To explore the repair effect of lycium barbarum polysaccharide (LBP) on ovarian injuries induced by repeated superovulation in mice, a model of ovarian injury was established, and ovarian repair was assessed after intragastric administration of LBP. The oocyte quality and blastocyst rates of pronuclear embryos in vitro were observed. The levels of 8-hydroxydeoxyguanosine (8-OHdG) and lipid peroxide (LPO) in ovarian tissue were measured, and ovarian damage was assessed in paraffin sections. The groups with significant injury were selected according to the above observation, mice in the significant injury group were intragastrically administered with LBP (low dose, 25 mg/kg; medium dose, 35 mg/kg; and high dose, 45 mg/kg) for 30 days. The above measurements and anti-Müllerian hormone (AMH) expression were detected in the mouse ovaries and the breeding verification was carried out. Our results showed that repeated superovulation could cause mouse oocyte quality to drop, significant differences started from 4 superovulation events (P < 0.05). The levels of 8-OHdG and LPO in the ovary increased gradually as the number of superovulation events increased, and significant differences were observed after 4-6 superovulations (P < 0.05). The ratios of primordial follicles, primary, tertiary and mature follicles decreased and the ratio of atresia follicles increased as the number of superovulation events increased, especially in 4-6 superovulation groups. Thus, the groups of superovulation 4-6 events were considered as significant injury groups. LBP-medium dose groups significantly improved the number and quantity of oocytes and embryo blastocyst rate (P < 0.05), significantly decreased 8-OHdG and LPO levels in mice ovary (P < 0.05), also improved the ratios of all stages follicles and reduced the rate of atresia follicles, increased the numbers of litter size, live birth, weaning survival, and repaired the expression of AMH in ovary significantly (P < 0.05). In conclusion, the degree of ovarian injury was affected by the number of superovulation. LBP repaired ovarian injuries most likely through scavenging oxidative products 8-OHdG and LPO and increasing AMH protein expression.

Current Status of Therapeutic Approaches against Peripheral Nerve Injuries: A Detailed Story from Injury to Recovery

Peripheral nerve injury is a complex condition with a variety of signs and symptoms such as numbness, tingling, jabbing, throbbing, burning or sharp pain. Peripheral nerves are fragile in nature and can easily get damaged due to acute compression or trauma which may lead to the sensory and motor functions deficits and even lifelong disability. After lesion, the neuronal cell body becomes disconnected from the axon's distal portion to the injury site leading to the axonal degeneration and dismantlement of neuromuscular junctions of targeted muscles. In spite of extensive research on this aspect, complete functional recovery still remains a challenge to be resolved. This review highlights detailed pathophysiological events after an injury to a peripheral nerve and the associated factors that can either hinder or promote the regenerative machinery. In addition, it throws light on the available therapeutic strategies including supporting therapies, surgical and non-surgical interventions to ameliorate the axonal regeneration, neuronal survival, and reinnervation of peripheral targets. Despite the availability of various treatment options, we are still lacking the optimal treatments for a perfect and complete functional regain. The need for the present age is to discover or design such potent compounds that would be able to execute the complete functional retrieval. In this regard, plant-derived compounds are getting more attention and several recent reports validate their remedial effects. A plethora of plants and plant-derived phytochemicals have been suggested with curative effects against a number of diseases in general and neuronal injury in particular. They can be a ray of hope for the suffering individuals.

Extraction, Structural Characterization, and Biological Functions of Lycium Barbarum Polysaccharides: A Review

Lycium barbarum polysaccharides (LBPs), as bioactive compounds extracted from L. barbarum L. fruit, have been widely explored for their potential health properties. The extraction and structural characterization methods of LBPs were reviewed to accurately understand the extraction method and structural and biological functions of LBPs. An overview of the biological functions of LBPs, such as antioxidant function, antitumor activity, neuroprotective effects, immune regulating function, and other functions, were summarized. This review provides an overview of LBPs and a theoretical basis for further studying and extending the applications of LBPs in the fields of medicine and food.

Eucommia ulmoides Oliv. Leaf Extract Improves Erectile Dysfunction in Streptozotocin-Induced Diabetic Rats by Protecting Endothelial Function and Ameliorating Hypothalamic-Pituitary-Gonadal Axis Function

Erectile dysfunction (ED) is a major complication of diabetes mellitus. Eucommia ulmoides Oliv. is used as a traditional medicine for male impotence, but no systematic study has examined its effect on diabetes-associated ED. In this study, we investigated the effects of Eucommia ulmoides Oliv. leaf extract (EULE) on restoring erectile function in streptozotocin (STZ)-induced diabetic rats model. After 16 weeks of treatment, EULE administration had significantly increased intracavernosal pressure, nitric oxide (NO) levels, and cyclic guanosine monophosphate (cGMP) concentrations. Serum superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) levels were markedly higher and serum malondialdehyde (MDA) levels were lower in the EULE-treated groups than in the diabetic model group. EULE restored NO biosynthesis by significantly increasing protein kinase B (Akt) and endothelial NO synthase (eNOS) activation. Furthermore, EULE is likely to benefit the hypothalamic-pituitary-gonadal (HPG) axis, as it increased gonadotropin-releasing hormone (GnRH), follicle-stimulating hormone (FSH), luteinizing hormone (LH), and testosterone (T) concentrations as well as hormone receptors Gnrhr, Fshr, and Lhr expression levels. Hence, EULE attenuates oxidative stress, increases NO production, and activates the Akt-eNOS pathway to restore endothelial function; moreover, EULE enhances the HPG axis to improve erectile function. These results suggest that EULE may represent a new therapeutic avenue for diabetes-associated ED.

Neural-like cells from adipose-derived stem cells for cavernous nerve injury in rats

Although the remaining nerve tissue can regenerate and partly restore erectile function when the cavernous nerve is compressed/severed and function lost, the limited regenerative ability of these nerve tissues often fails to meet clinical needs. Adipose-derived stem cells are easy to obtain and culture, and can differentiate into neural cells. Their proliferation rate is easy to control and they may be used to help restore injured cavernous nerve function. Sprague-Dawley male rats (n = 45) were equally randomized into three groups: fifteen rats as a sham-operated group, fifteen rats as a bilateral nerve crush (BINC) group (with no further intervention), fifteen rats as a BINC with intracavernous injection of one million neural-like cells from adipose-derived stem cells (NAS) (BINC + NAS) group. After 4 weeks, erectile function was assessed by stimulating the cavernous body. The number of myelinated axons in the dorsal cavernous nerve was determined by toluidine blue staining. The area of neuronal nitric oxide synthase-positive fibers in the dorsal penile nerve was measured by immunohistochemical staining. Masson staining was used to analyze the ratio of smooth muscle to collagen in penile tissue. The results demonstrate that maximal intracavernous pressure, the ratio of maximal intracavernous pressure to mean arterial pressure, the numbers of myelinated axons and neuronal nitric oxide synthase-positive fibers in the dorsal penile nerve, and the ratio of smooth muscle to collagen could be increased after cell transplantation. These findings indicate that neural-like cells from adipose-derived stem cells can effectively alleviate cavernous nerve injury and improve erectile function. All animal experiments were approved by the Animal Ethics Committee of Huazhong University of Science and Technology, China (approval No. 2017-1925) on September 15, 2017.

Traditional Chinese medical therapy for erectile dysfunction

Traditional Chinese medicine (TCM), including acupuncture and Chinese herbs, is used as an alternative therapy to increase the curative effect for erectile dysfunction (ED). A large number of studies have been conducted to investigate the effect and mechanism of TCM for treating ED. The therapeutic effect of acupuncture on ED is still controversial at present. However, some Chinese herbs exhibited satisfying outcomes and they might improve erectile function by activating nitric oxide synthase (NOS)-cyclic guanosine monophosphate (cGMP) pathway, increasing cyclic adenosine monophosphate (cAMP) expression, elevating testosterone level, reducing intracellular Ca²⁺ concentration, down-regulating transforming growth factor β1 (TGFβ1)/Smad2 signaling pathway, or ameliorating the oxidative stress.