Topically applied NO-releasing nanoparticles can increase intracorporal pressure and elicit spontaneous erections in a rat model of radical prostatectomy

An overview of conventional and investigational phosphodiesterase 5 inhibitors for treating erectile dysfunction and other conditions

INTRODUCTION

There is a rising concern about developing innovative, efficacious PDE5I molecules that provide better safety, efficacy, and tolerability with less adverse effects. Innovative PDE5I with dual targets have also been defined in the literature. Additionally, some of PDE5I are able to selectively inhibit other enzymes such as histone deacetylase, acetylcholine esterase, and cyclooxygenase or act as nitric oxide donors. This review presents knowledge concerning the advanced trends and perspectives in using PDE5I in treatment of ED and other conditions.

AREAS COVERED

Pre-clinical and early clinical trials that investigated the safety, efficacy, and tolerability of novel PDE5I such as Udenafil, Mirodenafil, Lodenafil, Youkenafil, Celecoxib, and TPN729 in treatment of ED and other conditions.

EXPERT OPINION

Preclinical and limited early clinical studies of the new molecules of PDE5I have demonstrated encouraging results; however, safety, efficacy, and tolerability are still issues that necessitate further long-term multicenter clinical studies to ensure justification of their uses in treatment of ED and other conditions. Progress in molecular delivery techniques and tailored patient-specific management and additional therapeutic technology will dramatically improve care for ED and other conditions. The dream of ED and many other conditions becoming more effectively managed may be feasible in the near future.

Dual Strategy with Adipose-Derived Stem Cells and l-arginine Recovered Cavernosal Functions in a Rat Model of Radical Prostatectomy

As standard therapy for prostate cancer, radical prostatectomy causes cavernous nerve (CN) injury and increases fibrosis and hypoxia-induced penile structural alterations. This study aimed to determine the potential beneficial effects of adipose-derived stem cells (ADSCs) and l-arginine alone or in combination on the penile erection in a rat model of erectile dysfunction caused by bilateral cavernous nerve transection (CNT). Male rats (n = 35) were randomized into five groups: Sham-operated; CNT (4-weeks); CNT plus ADSCs (1 × 106 cells by intracavernosal injection); CNT plus l-arginine (4 weeks, 10 mg/kg/day, oral); and ADSCs combined with l-arginine in CNT. In vivo erectile responses and in vitro relaxant responses were measured. Western blot and immunohistochemistry analyses were used to determine the expression and localization of endothelial nitric oxide synthase, neuronal nitric oxide synthase, transforming growth factor-beta 1, hypoxia-inducible factor-1 alpha (HIF-1α), and apoptosis markers (Bax and Bcl-2). The ratio of smooth muscle to collagen and nerve regeneration were calculated using Masson's trichrome and nicotinamide adenine dinucleotide phosphate (NADPH)-diaphorase staining. The combined treatment restored diminished erectile responses, endothelium-dependent acetylcholine, and electrical field stimulation-induced relaxation of the corpus cavernosum in rats with CNT, whereas either monotherapy produced only partial improvements. All treatment regimens restored increases in the protein expression of HIF-1 and Bax in rats with CNT. The decrease in smooth muscle mass and NADPH-diaphorase-positive nerve fibers was partially ameliorated by monotherapy, whereas combined therapy led to recovery. These findings indicate that combined treatment with ADSCs and l-arginine may restore erectile function in rats with CNT by inhibiting hypoxia-induced neurotoxicity and preserving endothelium function and smooth muscle content.

Ultrasound-targeted microbubble destruction mediates PDE5i/NO integration for cavernosum remodeling and penile rehabilitation

Erectile dysfunction (ED) caused by cavernous nerve injury (CNI) is refractory to heal mainly ascribed to the adverse remodeling of the penis induced by ineffectual microvascular perfusion, fibrosis, and neurotrophins scarcity in cavernosum. Phosphodiesterase type V inhibitors (PDE5i) have been regarded as an alternative candidate drug for avoiding penile neuropathy. However, the therapeutic efficacy is severely limited due to poor accumulation under systemic medication and endogenous nitric oxide (NO) deficiency in cavernosum. Herein, an innovative liposomal microbubble (MB) loaded with both Sildenafil (one of PDE5i) and NO was designed. Ultrasound-targeted MB destruction (UTMD)-mediated efficient release and integration erectogenic agents into corpus cavernosum with high biosafety. On a bilateral CNI rat model, the multifunctional MB-cooperated UTMD improved microvascular perfusion in penis, simultaneously, alleviated hypoxia and oxidative stress, indicating successful activation of NO-cyclic guanosine monophosphate pathway. Also, evaluation of the endothelial/muscular composition, intracavernosal pressure, and neural integrity in the penis proved that coordinated intervention reversed the abnormal structural remodeling and promoted the recovery of functional erection. Our work demonstrates that MB loading Sildenafil and NO combined with UTMD hold great promise to "awaken" the efficacy of PDE5i in neurogenic ED, which provided a superior option for ensuring penile rehabilitation.

Advanced hydrogels: New expectation for the repair of organic erectile dysfunction

Organic erectile dysfunction (ED) is a type of sexual disorder in men that is usually associated with illness, surgical injury, normal aging and has a high incidence across the globe. And the essence of penile erection is a neurovascular event regulated by a combination of factors. Nerve and vascular injury are the main causes of erectile dysfunction. Currently, the main treatment options for ED include phosphodiesterase type 5 inhibitors (PDE5Is), intracorporeal injections and vacuum erection devices (VEDs), which are ineffective. Therefore, it is essential to find an emerging, non-invasive and effective treatment for ED. The histopathological damage causing ED can be improved or even reversed with hydrogels, in contrast to current therapies. Hydrogels have many advantages, they can be synthesized from various raw materials with different properties, possess a definite composition, and have good biocompatibility and biodegradability. These advantages make hydrogels an effective drug carrier. In this review, we began with an overview of the underlying mechanisms of organic erectile dysfunction, discussed the dilemmas of existing treatments for ED, and described the unique advantages of hydrogel over other approaches. Then emphasizing the progress of research on hydrogels in the treatment of ED.

Nanotechnology as a tool to advance research and treatment of non-oncologic urogenital diseases

Nanotechnology represents an expanding area of research and innovation in almost every field of science, including Medicine, where nanomaterial-based products have been developed for diagnostic and therapeutic applications. Because of their small, nanoscale size, these materials exhibit unique physical and chemical properties that differ from those of each component when considered in bulk. In Nanomedicine, there is an increasing interest in harnessing these unique properties to engineer nanocarriers for the delivery of therapeutic agents. Nano-based drug delivery platforms have many advantages over conventional drug administration routes as this technology allows for local and transdermal applications of therapeutics that can bypass the first-pass metabolism, improves drug efficacy through encapsulation of hydrophobic drugs, and allows for a sustained and controlled release of encapsulated agents. In Urology, nano-based drug delivery platforms have been extensively investigated and implemented for cancer treatment. However, there is also great potential for use of nanotechnology to treat non-oncologic urogenital diseases. We provide an update on research that is paving the way for clinical translation of nanotechnology in the areas of erectile dysfunction (ED), overactive bladder (OAB), interstitial cystitis/bladder pain syndrome (IC/BPS), and catheter-associated urinary tract infections (CAUTIs). Overall, preclinical and clinical studies have proven the utility of nanomaterials both as vehicles for transdermal and intravesical delivery of therapeutic agents and for urinary catheter formulation with antimicrobial agents to treat non-oncologic urogenital diseases. Although clinical translation will be dependent on overcoming regulatory challenges, it is inevitable before there is universal adoption of this technology to treat non-oncologic urogenital diseases.

Erectile dysfunction resulting from pelvic surgery is associated with changes in cavernosal gene expression indicative of cavernous nerve injury

Pelvic surgery, even without direct cavernous nerve injury, carries a high risk of post-operative erectile dysfunction. The present studies were aimed at identifying molecular mechanisms by which pelvic surgery results in erectile dysfunction. As a model of pelvic surgery, male Sprague-Dawley rats underwent pelvic laparotomy, avoiding direct cavernous nerve injury. A second group of animals, serving as a model of direct cavernous nerve injury, underwent bilateral transection of the cavernous nerve. Cavernosometry demonstrated, that even in the absence of direct nerve injury, the pelvic surgery model exhibited significant erectile dysfunction 3 days post-operatively. Gene expression profiling also demonstrated that even in this animal model of nerve-sparing pelvic surgery, the profile of differentially expressed genes in cavernosal tissue was indicative of cavernous nerve injury. In addition, although 6 hr after surgery there were significant changes in circulating cytokine/chemokine levels, an inflammatory response in the major pelvic ganglion, cavernous nerve and cavernosal tissue was only observed 3 days post-surgery. Our results validate a rat model of pelvic surgery exhibiting erectile dysfunction and suggest systemic release of cytokines/chemokines following surgical trauma might mediate a pathological inflammatory response in tissues distal to the site of surgical trauma, indirectly resulting in cavernous nerve injury and erectile dysfunction.

Advances in Nanoparticle Delivery System for Erectile Dysfunction: An Updated Review

INTRODUCTION

The use of current available treatment for male erectile dysfunction (ED) has some limitations that are related to efficacy and adverse effects. Nanotechnology has been used as a new tool in medicine to improve these limitations and new medications potentially to alleviate and cure ED.

AIM

To review the currently literature on new nano medications for ED based on scientific and clinical studies, efficacy, safety, mechanisms of action, and to identify gaps for future research.

METHODS

A comprehensive literature review was conducted via Google Scholar, Science Direct, and PubMed on English publications using different keywords such as "erectile dysfunction", "emerging treatments", "nanotechnology", and "herbal medicine". The retrieved papers were organized into groups according to the sections covered in this review paper.

MAIN OUTCOMES MEASURES

We reviewed novel ED treatments such as nanotechnological phosphodiesterase inhibitors, papaverine hydrochloride, sialorphin, adipose tissue-derived stem cells, sonic hedgehog, and herbal medicine.

RESULTS

Numerous preclinical studies have addressed novel phosphodiesterase 5 inhibitors nanoparticle, and their recent delivery systems. Nitric oxide, sialorphin, sonic hedgehog, and herbal medicine loaded nanoparticles and nano adipose tissue-derived stem cells as a potential new treatment for ED. In addition, papaverine-containing nanoparticles have been reported. A limited number of randomized clinical studies have determined the mechanism of these treatments.

CONCLUSION

A literature review on the application of nanotechnology in ED therapy was successfully conducted. New nano medications are promising to treat ED. However, further studies are warranted to further assess their efficacy and safety. Masuku NP, Unuofin JO, Lebelo SL. Advances in Nanoparticle Delivery System for Erectile Dysfunction: An Updated Review. Sex Med 2021;XX:XXXXXX.

Topically delivered nitric oxide acts synergistically with an orally administered PDE5 inhibitor in eliciting an erectile response in a rat model of radical prostatectomy

Patients undergoing radical prostatectomy (RP) have a high incidence of post-operative erectile dysfunction (ED) refractory to treatment by oral phosphodiesterase-type-5-inhibitors (PDE5i). In the present studies, we investigated if a topically applied, nitric oxide microparticle delivery system (NO-MP) might act synergistically with an oral PDE5i (sildenafil) to improve erectile function outcomes in a rat model of RP.

Thirty-five Sprague–Dawley rats underwent bilateral transection of the cavernous nerve (CN) for one week. After one-week, animals were orally administered 0, 0.05 or 0.005 mg sildenafil/kg and the erectile response following topical application to the penile shaft of 250mg or 100mg NO-MP, or blank-MP, was monitored over a two-hour timeframe by recording the intracorporal pressure normalized to systemic blood pressure (ICP/BP, N=5 animals/treatment group).

Oral treatment with sildenafil by itself resulted in no observable erectile response. However, a combination of orally administered 0.05 sildenafil/kg with topical application of 250mg NO-MP, compared to 250 mg NO-MP by itself, resulted in significantly more spontaneous erections (4.6 compared to 2 erections per hour, t-test; p-value = 0.043), with a significantly faster onset for the first erectile response (11 compared to 22 minutes; t-test, p-value = 0.041).

Our results demonstrate a synergistic effect between orally administered PDE5i and topically applied NO-MP in eliciting an erectile response. Furthermore, they suggest a potential novel therapeutic approach to treat men with ED resulting from RP, through combination therapy of a topically applied NO-MP and an orally administered PDE5i.

Effect of penile rehabilitation with low intensity extracorporeal shock wave therapy on erectile function recovery following robot-assisted laparoscopic prostatectomy

BACKGROUNDS

Considering the natural course of cavernous nerve recovery after robot-assisted laparoscopic prostatectomy (RALP), early intervention of low intensity extracorporeal shock wave therapy (LIESWT) would be more effective for enhancing overall recovery of sexual function (SF). Our objective of this study is to analyze longitudinally the alterations of SF in patients after RALP, with a focus on the effect of early and delayed intervention with LIESWT.

METHODS

A total of 5 and 11 patients underwent early and delayed intervention with LIESWT, respectively. SF was assessed with the Expanded Prostate Cancer Index Composite (EPIC). The same surgeon performed RALP on 178 patients, and these patients were assigned to the non-LIESWT group to establish a control group. The SF score of EPIC was investigated longitudinally before RALP and 3, 6, 9, and 12 months after RALP.

RESULTS

Our results show that penile rehabilitation with LIESWT immediately before urethral catheter removal improved SF scores. In the baseline, the SF score was significantly higher in the early LIESWT group (P=0.0001). The SF score was significantly lower at postoperative 6 months (early 19.2, delayed 17.9, and non-LIESWT 8.1; P=0.0171), 9 months (20.9, 25.8, and 10.2; P=0.0188), and 12 months (28.0, 21.3, and 9.5; P=0.0051) in the non-LIESWT group. We regret that there was no significant difference in the recovery of SF between the early and delayed protocol with LIESWT at all points. In keeping with our results, LIESWT demonstrated the potential to be efficacious in treatment options for severe post-radical prostatectomy (RP) erectile dysfunction (ED) as it may indirectly support its promotion of nerve regeneration in severe ED due to RP.

CONCLUSIONS

This is the first study in which LIESWT has been shown to deliver a clinical benefit on its early or delayed intervention to patients after RALP to penile rehabilitation in terms of restoring SF. Our preliminary results suggest that LIESWT could be used as a treatment option in penile rehabilitation.

Effect of penile rehabilitation with low intensity extracorporeal shock wave therapy on erectile function recovery following robot-assisted laparoscopic prostatectomy

Backgrounds

Considering the natural course of cavernous nerve recovery after robot-assisted laparoscopic prostatectomy (RALP), early intervention of low intensity extracorporeal shock wave therapy (LIESWT) would be more effective for enhancing overall recovery of sexual function (SF). Our objective of this study is to analyze longitudinally the alterations of SF in patients after RALP, with a focus on the effect of early and delayed intervention with LIESWT.

Methods

A total of 5 and 11 patients underwent early and delayed intervention with LIESWT, respectively. SF was assessed with the Expanded Prostate Cancer Index Composite (EPIC). The same surgeon performed RALP on 178 patients, and these patients were assigned to the non-LIESWT group to establish a control group. The SF score of EPIC was investigated longitudinally before RALP and 3, 6, 9, and 12 months after RALP.

Results

Our results show that penile rehabilitation with LIESWT immediately before urethral catheter removal improved SF scores. In the baseline, the SF score was significantly higher in the early LIESWT group (P=0.0001). The SF score was significantly lower at postoperative 6 months (early 19.2, delayed 17.9, and non-LIESWT 8.1; P=0.0171), 9 months (20.9, 25.8, and 10.2; P=0.0188), and 12 months (28.0, 21.3, and 9.5; P=0.0051) in the non-LIESWT group. We regret that there was no significant difference in the recovery of SF between the early and delayed protocol with LIESWT at all points. In keeping with our results, LIESWT demonstrated the potential to be efficacious in treatment options for severe post-radical prostatectomy (RP) erectile dysfunction (ED) as it may indirectly support its promotion of nerve regeneration in severe ED due to RP.

Conclusions

This is the first study in which LIESWT has been shown to deliver a clinical benefit on its early or delayed intervention to patients after RALP to penile rehabilitation in terms of restoring SF. Our preliminary results suggest that LIESWT could be used as a treatment option in penile rehabilitation.

Drug delivery options and therapeutic advances in the management of erectile dysfunction

INTRODUCTION

Erectile dysfunction (ED) is defined as the inability to achieve or maintain an erection sufficient for satisfactory sexual performance. It is estimated that 20-30% of adult men will have at least one episode of ED during their lifetime and the prevalence increases with age. ED is known to have significant negative psychological implications for men, resulting in impaired functional status and a greater prevalence of anxiety and depression.

AREAS COVERED

Medications for the treatment of erectile dysfunction largely revolve around oral, injection, and topical therapies. Though all three modalities are widely used, each delivery option has its own advantages and specific indications. Likewise, there are several new developing treatments for ED that may change the landscape of treatment. The goal of this review is to summarize contemporary drug delivery options used in the treatment of ED and highlight future promising pharmacological developments.

EXPERT OPINION

There are a myriad of new developments on the horizon including new PDE5Is and drug targets, nanotechnology enhancements, stem cell and gene therapy, shockwave therapy, and platelet-rich plasma injections. These are all promising new methods to not only treat ED but also to address the pathology and prevent or eliminate further damage.

NO-Releasing Nanoparticles Ameliorate Detrusor Overactivity in Transgenic Sickle Cell Mice via Restored NO/ROCK Signaling

Sickle cell disease (SCD) is associated with overactive bladder (OAB). Detrusor overactivity, a component of OAB, is present in an SCD mouse, but the molecular mechanisms for this condition are not well-defined. We hypothesize that nitric oxide (NO)/ ras homolog gene family (Rho) A/Rho-associated kinase (ROCK) dysregulation is a mechanism for detrusor overactivity and that NO-releasing nanoparticles (NO-nps), a novel NO delivery system, may serve to treat this condition. Male adult SCD transgenic, combined endothelial NO synthases (eNOSs) and neuronal NOS (nNOS) gene-deficient (dNOS^-/-), and wild-type (WT) mice were used. Empty nanoparticle or NO-np was injected into the bladder, followed by cystometric studies. The expression levels of phosphorylated eNOS (Ser-1177), protein kinase B (Akt) (Ser-473), nNOS (Ser-1412), and myosin phosphatase target subunit 1 (MYPT1) (Thr-696) were assessed in the bladder. SCD and dNOS^-/- mice had a greater (P < 0.05) number of voiding and nonvoiding contractions compared with WT mice, and they were normalized by NO-np treatment. eNOS (Ser-1177) and AKT (Ser-473) phosphorylation were decreased (P < 0.05) in the bladder of SCD compared with WT mice and reversed by NO-np. Phosphorylated MYPT1, a marker of the RhoA/ROCK pathway, was increased (P < 0.05) in the bladder of SCD mice compared with WT and reversed by NO-np. nNOS phosphorylation on positive (Ser-1412) regulatory site was decreased (P < 0.05) in the bladder of SCD mice compared with WT and was not affected by NO-np. NO-nps did not affect any of the measured parameters in WT mice. In conclusion, dysregulation of NO and RhoA/ROCK pathways is associated with detrusor overactivity in SCD mice; NO-np reverses these molecular derangements in the bladder and decreases detrusor overactivity. SIGNIFICANCE STATEMENT: Voiding abnormalities commonly affect patients with sickle cell disease (SCD) but are problematic to treat. Clarification of the science for this condition in an animal model of SCD may lead to improved interventions for it. Our findings suggest that novel topical delivery of a vasorelaxant agent nitric oxide into the bladder of these mice corrects overactive bladder by improving deranged bladder physiology regulatory signaling.

Topical nitric oxide releasing nanoparticles are effective in a murine model of dermal Trichophyton rubrum dermatophytosis

Systemic therapies are preferred for treating dermal dermatophytosis due to inadequate penetration of topical agents. However, systemic antifungals are associated with off-target effects and limited tissue penetration, and antimicrobial resistance is a growing concern. To address this, we investigated topical nitric oxide-releasing nanoparticles (NO-np), which have been used against superficial fungal infections and bacterial abscesses. In addition to enhanced penetration and permeation conferred by nanoparticles, nitric oxide, a broad-spectrum multi-mechanistic antimicrobial agent, offers decreased likelihood of resistance development. In the current study, NO-np inhibited Trichophyton rubrum in vitro, as well as in a murine model of dermal dermatophytosis. In mice, NO-np reduced fungal burden after three days, with complete clearance after seven. Furthermore, NO-np decreased tissue IL-2, 6, 10 and TNFα, indicating earlier attenuation of the host inflammatory response and decreased tissue morbidity. Thus, topical NO-np represent an attractive alternative to systemic therapy against dermal T. rubrum infection.

Role of Nanotechnology in Erectile Dysfunction Treatment

INTRODUCTION

The biological importance of nanotechnology-based delivery vehicles for in vivo tissue regeneration is gaining acceptance by the medical community; however, its relevance and incorporation into the treatment of sexual dysfunction are evolving and have not been well evaluated.

AIM

To provide scientific evidence examining the use of state-of-the-art nanotechnology-based delivery methodology in the treatment of erectile dysfunction (ED) in animal models and in patients.

METHODS

This review assessed the current basic science literature examining the role of nanotechnology-based delivery vehicles in the development of potential ED therapies.

RESULTS

There are four primary areas where nanotechnology has been applied for ED treatment: (i) topical delivery of drugs for on-demand erectile function, (ii) injectable gels into the penis to prevent morphologic changes after prostatectomy, (iii) hydrogels to promote cavernous nerve regeneration or neuroprotection, and (iv) encapsulation of drugs to increase erectile function (primarily of phosphodiesterase type 5 inhibitors).

CONCLUSION

Basic science studies provide evidence for a significant and evolving role for nanotechnology in the development of therapies for ED and suggest that properly administered nano-based therapies might be advantageous for treating male sexual dysfunction.

HbE/β-Thalassemia and Oxidative Stress: The Key to Pathophysiological Mechanisms and Novel Therapeutics

SIGNIFICANCE

Oxidative stress and generation of free radicals are fundamental in initiating pathophysiological mechanisms leading to an inflammatory cascade resulting in high rates of morbidity and death from many inherited point mutation-derived hemoglobinopathies. Hemoglobin (Hb)E is the most common point mutation worldwide. The βE-globin gene is found in greatest frequency in Southeast Asia, including Thailand, Malaysia, Indonesia, Vietnam, Cambodia, and Laos. With the wave of worldwide migration, it is entering the gene pool of diverse populations with greater consequences than expected.

CRITICAL ISSUES

While HbE by itself presents as a mild anemia and a single gene for β-thalassemia is not serious, it remains unexplained why HbE/β-thalassemia (HbE/β-thal) is a grave disease with high morbidity and mortality. Patients often exhibit defective physical development, severe chronic anemia, and often die of cardiovascular disease and severe infections. Recent Advances: This article presents an overview of HbE/β-thal disease with an emphasis on new findings pointing to pathophysiological mechanisms derived from and initiated by the dysfunctional property of HbE as a reduced nitrite reductase concomitant with excess α-chains exacerbating unstable HbE, leading to a combination of nitric oxide imbalance, oxidative stress, and proinflammatory events.

FUTURE DIRECTIONS

Additionally, we present new therapeutic strategies that are based on the emerging molecular-level understanding of the pathophysiology of this and other hemoglobinopathies. These strategies are designed to short-circuit the inflammatory cascade leading to devastating chronic morbidity and fatal consequences. Antioxid. Redox Signal. 26, 794-813.

Biodegradable Nanoparticles for Delivery of Therapeutics in CNS Infection

Despite the significant advances in neurological medicine, it remains difficult to treat ailments directly involving the brain. The blood brain barrier (BBB) is a tightly regulated, selectively permeable barrier that restricts access from the blood into the brain extracellular fluid (BEF). Many conditions such as tumors or infections in the brain are difficult to treat due to the fact that drugs and other therapeutic agents are unable to easily pass through this relatively impermeable barrier. Human Immunodeficiency Virus (HIV) presents a particular problem as it is able to remain dormant in the brain for years protected from antiretroviral drugs by the BBB. The development of nanoscale carriers over the past few decades has made possible the delivery of therapies with the potential to overcome membrane barriers and provide specific, targeted delivery. This review seeks to provide a comprehensive overview of the various aspects of nanoparticle formulation and their applications in improving the delivery efficiency of drugs, specifically antiretroviral therapeutics to the brain to treat HIV.

Curcumin slows osteoarthritis progression and relieves osteoarthritis-associated pain symptoms in a post-traumatic osteoarthritis mouse model

Background

Curcumin has been shown to have chondroprotective potential in vitro. However, its effect on disease and symptom modification in osteoarthritis (OA) is largely unknown. This study aimed to determine whether curcumin could slow progression of OA and relieve OA-related pain in a mouse model of destabilization of the medial meniscus (DMM).

Methods

Expression of selected cartilage degradative-associated genes was evaluated in human primary chondrocytes treated with curcumin and curcumin nanoparticles and assayed by real-time PCR. The mice subjected to DMM surgery were orally administered curcumin or topically administered curcumin nanoparticles for 8 weeks. Cartilage integrity was evaluated by Safranin O staining and Osteoarthritis Research Society International (OARSI) score, and by immunohistochemical staining of cleaved aggrecan and type II collagen, and levels of matrix metalloproteinase (MMP)-13 and ADAMTS5. Synovitis and subchondral bone thickness were scored based on histologic images. OA-associated pain and symptoms were evaluated by von Frey assay, and locomotor behavior including distance traveled and rearing.

Results

Both curcumin and nanoparticles encapsulating curcumin suppressed mRNA expression of pro-inflammatory mediators IL-1β and TNF-α, MMPs 1, 3, and 13, and aggrecanase ADAMTS5, and upregulated the chondroprotective transcriptional regulator CITED2, in primary cultured chondrocytes in the absence or presence of IL-1β. Oral administration of curcumin significantly reduced OA disease progression, but showed no significant effect on OA pain relief. Curcumin was detected in the infrapatellar fat pad (IPFP) following topical administration of curcumin nanoparticles on the skin of the injured mouse knee. Compared to vehicle-treated controls, topical treatment led to: (1) reduced proteoglycan loss and cartilage erosion and lower OARSI scores, (2) reduced synovitis and subchondral plate thickness, (3) reduced immunochemical staining of type II collagen and aggrecan cleavage epitopes and numbers of chondrocytes positive for MMP-13 and ADAMTS5 in the articular cartilage, and (4) reduced expression of adipokines and pro-inflammatory mediators in the IPFP. In contrast to oral curcumin, topical application of curcumin nanoparticles relieved OA-related pain as indicated by reduced tactile hypersensitivity and improved locomotor behavior.

Conclusion

This study provides the first evidence that curcumin significantly slows OA disease progression and exerts a palliative effect in an OA mouse model.

Electronic supplementary material

The online version of this article (doi:10.1186/s13075-016-1025-y) contains supplementary material, which is available to authorized users.

Developments in the management of Chagas cardiomyopathy

Over 100 years have elapsed since the discovery of Chagas disease and there is still much to learn regarding pathogenesis and treatment. Although there are antiparasitic drugs available, such as benznidazole and nifurtimox, they are not totally reliable and often toxic. A recently released negative clinical trial with benznidazole in patients with chronic Chagas cardiomyopathy further reinforces the concerns regarding its effectiveness. New drugs and new delivery systems, including those based on nanotechnology, are being sought. Although vaccine development is still in its infancy, the reality of a therapeutic vaccine remains a challenge. New ECG methods may help to recognize patients prone to developing malignant ventricular arrhythmias. The management of heart failure, stroke and arrhythmias also remains a challenge. Although animal experiments have suggested that stem cell based therapy may be therapeutic in the management of heart failure in Chagas cardiomyopathy, clinical trials have not been promising.

Development and therapeutic applications of nitric oxide releasing materials to treat erectile dysfunction

The role of nitric oxide (NO) in erectile physiology is well documented. NO activates relaxation of corporal cavernosal smooth muscle tissue resulting in increased blood flow into the penis resulting in an erection. At present, pharmacologic treatments for erectile dysfunction, such as the phosphodiesterase-5 inhibitors, potentiate the erectile response generated by NO. However, a new class of treatments at a preclinical stage may allow localized delivery of NO to the penis via cutaneous application. These treatments may be of particular value to patients with a neurogenic component to their erectile dysfunction, and may act synergistically with phosphodiesterase-5 inhibitors to increase their efficacy.