Stem-cell therapy and platelet-rich plasma in regenerative medicines: A review on pros and cons of the technologies

The efficacy of platelet rich plasma in the treatment of erectile dysfunction: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Erectile dysfunction (ED) is a common issue among males, and the use of platelet-rich plasma (PRP) therapy for treating ED has gained increasing attention, but there is still no conclusive evidence regarding its efficacy.

AIM

To evaluate the efficacy of PRP therapy for ED.

METHODS

We systematically searched PubMed, Embase, Cochrane Library, and Web of Science databases up to November 2023 to identify randomized controlled trials (RCTs) on PRP therapy for ED. We used Review Manager version 5.4 for data analysis and management.

RESULT

After applying inclusion and exclusion criteria for screening, a total of 4 studies involving 413 patients were finally included in our meta-analysis. According to our analysis, the PRP group showed significant advantages over the placebo group in terms of MCID at the first month (p = 0.03) and sixth months (p = 0.008), while there was no significant difference between the two groups at the third month (p = 0.19). Additionally, in terms of IIEF, PRP showed significantly better efficacy than placebo at the first, third, and sixth months (p < 0.00001).

CONCLUSIONS

PRP shows more effectiveness in treating ED compared to placebo, offering hope as a potential alternative treatment for ED.

Regenerative Therapy in Erectile Dysfunction: A Survey on Current Global Practice Trends and GAF Expert Recommendations

PURPOSE

This study aimed to examine current global practices in regenerative therapy (RT) for erectile dysfunction (ED) and to establish expert recommendations for its use, addressing the current lack of solid evidence and standardized guidelines.

MATERIALS AND METHODS

A 39-question survey was developed by senior Global Andrology Forum (GAF) experts to comprehensively cover clinical aspects of RT. This was distributed globally via a secure online Google Form to ED specialists through the GAF website, international professional societies, and social media, the responses were analyzed and presented for frequencies as percentages. Consensus on expert recommendations for RT use was achieved using the Delphi method.

RESULTS

Out of 479 respondents from 62 countries, a third reported using RT for ED. The most popular treatment was low-intensity shock wave therapy (54.6%), followed by platelet-rich plasma (24.5%) and their combination (14.7%), with stem cell therapy being the least used (3.7%). The primary indication for RT was the refractory or adverse effects of PDE5 inhibitors, with the best effectiveness reported in middle-aged and mild-to-moderate ED patients. Respondents were confident about its overall safety, with a significant number expressing interest in RT's future use, despite pending guidelines support.

CONCLUSIONS

This inaugural global survey reveals a growing use of RT in ED treatment, showcasing its diverse clinical applications and potential for future widespread adoption. However, the lack of comprehensive evidence and clear guidelines requires further research to standardize RT practices in ED treatment.

Evolution of biotechnological advances and regenerative therapies for endometrial disorders: a systematic review

BACKGROUND

The establishment and maintenance of pregnancy depend on endometrial competence. Asherman syndrome (AS) and intrauterine adhesions (IUA), or endometrial atrophy (EA) and thin endometrium (TE), can either originate autonomously or arise as a result from conditions (i.e. endometritis or congenital hypoplasia), or medical interventions (e.g. surgeries, hormonal therapies, uterine curettage or radiotherapy). Affected patients may present an altered or inadequate endometrial lining that hinders embryo implantation and increases the risk of poor pregnancy outcomes and miscarriage. In humans, AS/IUA and EA/TE are mainly treated with surgeries or pharmacotherapy, however the reported efficacy of these therapeutic approaches remains unclear. Thus, novel regenerative techniques utilizing stem cells, growth factors, or tissue engineering have emerged to improve reproductive outcomes.

OBJECTIVE AND RATIONALE

This review comprehensively summarizes the methodologies and outcomes of emerging biotechnologies (cellular, acellular, and bioengineering approaches) to treat human endometrial pathologies. Regenerative therapies derived from human tissues or blood which were studied in preclinical models (in vitro and in vivo) and clinical trials are discussed.

SEARCH METHODS

A systematic search of full-text articles available in PubMed and Embase was conducted to identify original peer-reviewed studies published in English between January 2000 and September 2023. The search terms included: human, uterus, endometrium, Asherman syndrome, intrauterine adhesions, endometrial atrophy, thin endometrium, endometritis, congenital hypoplasia, curettage, radiotherapy, regenerative therapy, bioengineering, stem cells, vesicles, platelet-rich plasma, biomaterials, microfluidic, bioprinting, organoids, hydrogel, scaffold, sheet, miRNA, sildenafil, nitroglycerine, aspirin, growth hormone, progesterone, and estrogen. Preclinical and clinical studies on cellular, acellular, and bioengineering strategies to repair or regenerate the human endometrium were included. Additional studies were identified through manual searches.

OUTCOMES

From a total of 4366 records identified, 164 studies (3.8%) were included for systematic review. Due to heterogeneity in the study design and measured outcome parameters in both preclinical and clinical studies, the findings were evaluated qualitatively and quantitatively without meta-analysis. Groups using stem cell-based treatments for endometrial pathologies commonly employed mesenchymal stem cells (MSCs) derived from the human bone marrow or umbilical cord. Alternatively, acellular therapies based on platelet-rich plasma (PRP) or extracellular vesicles are gaining popularity. These are accompanied by the emergence of bioengineering strategies based on extracellular matrix (ECM)-derived hydrogels or synthetic biosimilars that sustain local delivery of cells and growth factors, reporting promising results. Combined therapies that target multiple aspects of tissue repair and regeneration remain in preclinical testing but have shown translational value. This review highlights the myriad of therapeutic material sources, administration methods, and carriers that have been tested.

WIDER IMPLICATIONS

Therapies that promote endometrial proliferation, vascular development, and tissue repair may help restore endometrial function and, ultimately, fertility. Based on the existing evidence, cost, accessibility, and availability of the therapies, we propose the development of triple-hit regenerative strategies, potentially combining high-yield MSCs (e.g. from bone marrow or umbilical cord) with acellular treatments (PRP), possibly integrated in ECM hydrogels. Advances in biotechnologies together with insights from preclinical models will pave the way for developing personalized treatment regimens for patients with infertility-causing endometrial disorders such as AS/IUA, EA/TE, and endometritis.

REGISTRATION NUMBER

https://osf.io/th8yf/.

Revolutionizing Back Pain Management: Is Epidural Platelet-Rich Plasma the Superior Choice Over Steroids?

Background and objective Low back discomfort is one of the main factors that restrict physical activity, and it is becoming more and more common. Surgery is the best option when all other conservative treatment methods have failed, but it is not a panacea. While local anesthetic-free and combined epidural steroid injections have been used for many years, their usefulness is limited to shorter periods. In the field of orthopedics, platelet-rich plasma (PRP) has gained widespread recognition as an adjuvant component. PRP has been applied to improve tissue repair, both soft and hard. This comparative study aimed to evaluate the potential of PRP as a therapy for low back pain (LBP). Methods We included 64 adult individuals with complaints of LBP. They were classified into two groups: group A underwent a single injection in the afflicted lumbar intervertebral disc (IVD) level with 1.5 ml of methylprednisolone, 1.5 ml 2% lidocaine, and 0.5 ml of saline under rigorous aseptic precautions; in contrast, group B was administered a single injection of 3 milliliters of autologous PRP. Patients' scores on the visual analog scale (VAS), the Modified Oswestry Disability Questionnaire (MODQ), and the Straight Leg Raising Test (SLRT) were assessed before and during therapy. Results The data gathered were subjected to statistical analysis. Statistically significant differences were found in the VAS scores between group A (methylprednisolone group) and group B (PRP group) post-one hour (6.0 ±0.74 vs. 6.92 ±0.57) and after three months (5.2 ±0.65 vs. 3.26 ±0.79). Conclusions Our study revealed gradual progressive improvement in the symptoms of patients in the PRP group as indicated by scores on SLRT, VAS, and MODQ. The results were comparable to those who received methylprednisolone injections. There was a statistically significant difference in VAS scores between the two groups, with the PRP group reporting a higher degree of pain reduction, showing that PRP is an effective alternative to epidural steroid infiltration in managing chronic LBP.

The Model of Interstitial Cystitis for Evaluating New Molecular Strategies of Interstitial Regeneration in Humans

Given the recent evidence in the clinical application of regenerative medicine, mostly on integumentary systems, we focused our interests on recent bladder regeneration approaches based on mesenchymal stem cells (MSCs), platelet-rich plasma (PRP), and hyaluronic acid (HA) in the treatment of interstitial cystitis/bladder pain syndrome (IC/BPS) in humans. IC/BPS is a heterogeneous chronic disease with not-well-understood etiology, characterized by suprapubic pain related to bladder filling and urothelium dysfunction, in which the impairment of immunological processes seems to play an important role. The histopathological features of IC include ulceration of the mucosa, edema, denuded urothelium, and increased detection of mast cells and other inflammatory cells. A deeper understanding of the molecular mechanism underlying this disease is essential for the selection of the right therapeutic approach. In fact, although various therapeutic strategies exist, no efficient therapy for IC/BPS has been discovered yet. This review gives an overview of the clinical and pathological features of IC/BPS, with a particular focus on the molecular pathways involved and a special interest in the ongoing few investigational therapies in IC/BPS, which use new regenerative medicine approaches, and their synergetic combination. Good knowledge of the molecular aspects related to stem cell-, PRP-, and biomaterial-based treatments, as well as the understanding of the molecular mechanism of this pathology, will allow for the selection of the right and best use of regenerative approaches of structures involving connective tissue and epithelia, as well as in other diseases.

The value of intraovarian autologous platelet rich plasma in women with poor ovarian reserve or ovarian insufficiency: a systematic review and meta-analysis

OBJECTIVES

To assess the value of intraovarian PRP in women with low ovarian reserve.

SEARCH STRATEGY

Screening of databases from inception to January 2023 using the keywords related to "Platelet-rich plasma" AND "poor ovarian reserve" OR "ovarian failure".

SELECTION CRITERIA

Fourteen studies (1632 participants) were included, 10 included women with POR, 1 included women with POI and 3 included both POR and POI women.

DATA COLLECTION AND ANALYSIS

Extracted data included study settings, design, sample size, population characteristics, volume, timing and preparation of PRP administration, and outcome parameters.

MAIN RESULTS

AMH level was evaluated in 11 studies (2099 women). The mean difference (MD) was 0.09 with 95% CI of - 0.06, 0.24 (P = 0.25). Antral follicular count level was assessed in 6 studies (1399 women). The MD was 1.73 with 95% CI of 0.81, 2.66 (P < 0.001). The number of oocytes retrieved was evaluated in 7 studies (1413 women). The MD was 1.21 with 95% CI of 0.48, 1.94 (P = 0.001).

CONCLUSION

This systematic review found a significant improvement of AFC, the number of retrieved oocytes, the number of cleavage embryos and the cancellation rate in women with POR.

TRIAL REGISTRATION

Registration number CRD42022365682.

Harnessing Healing Power: A Comprehensive Review on Platelet-Rich Plasma in Compound Fracture Care

This comprehensive review explores the applications of platelet-rich plasma (PRP) in the context of compound fracture care, providing a thorough examination of its biological mechanisms, preparation techniques, and clinical implications. The analysis highlights PRP's potential in accelerating bone healing, enhancing soft tissue repair, reducing inflammation and infection risks, and managing pain during fracture recovery. The review underscores the importance of ethical and regulatory considerations in integrating PRP into orthopaedic practice, emphasising informed consent, transparent patient communication, and ongoing monitoring of ethical concerns. Looking ahead, the implications for the future of compound fracture care suggest a transformative shift with the potential for personalised medicine approaches and emerging technologies. However, the conclusion calls for a balanced perspective, acknowledging the promising applications of PRP while emphasising the need for responsible and ethical use. The collaborative efforts of healthcare professionals, researchers, and regulatory bodies are crucial in navigating this evolving landscape and harnessing the healing power of PRP to redefine orthopaedic care for individuals with compound fractures.

Application of Platelet-Rich Plasma as a Stem Cell Treatment - an Attempt to Clarify a Common Public Misconception

In recent years, there has been a significant increase in the practice of regenerative medicine by health practitioners and direct-to-consumer businesses globally. Among different tools of regenerative medicine, platelet-rich plasma (PRP) and stem cell-based therapies have received considerable attention. The use of PRP, in particular, has gained popularity due to its easy access, simple processing techniques, and regenerative potential. However, it is important to address a common misconception amongst the general public equating to PRP and stem cells due to the demonstrated efficacy of PRP in treating musculoskeletal and dermatological disorders. Notably, PRP promotes regeneration by providing growth factors or other paracrine factors only. Therefore, it cannot replenish or replace the lost cells in conditions where a large number of cells are required to regenerate tissues and/or organs. In such cases, cellbased therapies are the preferred option. Additionally, other tools of regenerative medicine, such as bioprinting, organoids, and mechanobiology also rely on stem cells for their success. Hence, healthcare and commercial entities offering direct-to-customer regenerative therapies should not mislead the public by claiming that the application of PRP is a stem cell-based therapy. Furthermore, it is important for regulatory bodies to strictly monitor these profit-driven entities to prevent them from providing unregulated regenerative treatments and services that claim a broad variety of benefits with little proof of efficacy, safety concerns, and obscure scientific justification.

The Synergistic Effects of Hyaluronic Acid and Platelet-Rich Plasma for Patellar Chondropathy

Musculoskeletal disorders are increasingly prevalent worldwide, causing significant socioeconomic burdens and diminished quality of life. Notably, patellar chondropathy (PC) is among the most widespread conditions affecting joint structures, resulting in profound pain and disability. Hyaluronic acid (HA) and platelet-rich plasma (PRP) have emerged as reliable, effective, and minimally invasive alternatives. Continuous research spanning from laboratory settings to clinical applications demonstrates the numerous advantages of both products. These encompass lubrication, anti-inflammation, and stimulation of cellular behaviors linked to proliferation, differentiation, migration, and the release of essential growth factors. Cumulatively, these benefits support the rejuvenation of bone and cartilaginous tissues, which are otherwise compromised due to the prevailing degenerative and inflammatory responses characteristic of tissue damage. While existing literature delves into the physical, mechanical, and biological facets of these products, as well as their commercial variants and distinct clinical uses, there is limited discussion on their interconnected roles. We explore basic science concepts, product variations, and clinical strategies. This comprehensive examination provides physicians with an alternative insight into the pathophysiology of PC as well as biological mechanisms stimulated by both HA and PRP that contribute to tissue restoration.

Current Review of Regenerative Medicine Therapies for Spine-Related Pain

PURPOSE OF REVIEW

Persistent spinal pain syndromes are pervasive and lead to functional impairment, increased healthcare utilization, potential disability, and high societal costs. Spinal (cervical, thoracic, lumbar, and sacroiliac joint) pain includes mechanical, degenerative, inflammatory, oncologic, and infectious etiologies. Regenerative medicine is a novel biotechnology targeting mechanical, degenerative, and inflammatory conditions believed to cause pain. Preparations including platelet-rich plasma, mesenchymal stem cells (adipose tissue and bone marrow aspirate concentrates), and growth factors are derived from an autologous donor. The goal of intervention through guided injection of the regenerative media is to reduce inflammation and reverse the degenerative cascade in hopes of restoring normal cellular composition (physiologic homeostasis) and anatomical function to improve pain and function. The authors review limited research supporting the use of platelet-rich plasma injections for facet joint arthropathy and sacroiliac joint pain compared to traditional steroid treatments, as well as the use of platelet rich plasma or mesenchymal stem cells for lumbar discogenic and radicular pain.

RECENT FINDINGS

Current evidence to support regenerative medicine for spine-related pain is limited. Although several studies demonstrated a reduction in pain, many of these studies had a small number of participants and were case series or prospective trials. Regenerative medicine treatments lack evidence for the treatment of spine-related pain. Large randomized controlled trials are needed with consistent study protocols to make further recommendations.

Preventative and therapeutic potential of tocotrienols on musculoskeletal diseases in ageing

Musculoskeletal health is paramount in an ageing population susceptible to conditions such as osteoporosis, arthritis and fractures. Age-related changes in bone, muscle, and joint function result in declining musculoskeletal health, reduced mobility, increased risk of falls, and persistent discomfort. Preserving musculoskeletal wellbeing is essential for maintaining independence and enhancing the overall quality of life for the elderly. The global burden of musculoskeletal disorders is significant, impacting 1.71 billion individuals worldwide, with age-related muscle atrophy being a well-established phenomenon. Tocotrienols, a unique type of vitamin E found in various sources, demonstrate exceptional antioxidant capabilities compared to tocopherols. This characteristic positions them as promising candidates for addressing musculoskeletal challenges, particularly in mitigating inflammation and oxidative stress underlying musculoskeletal disorders. This review paper comprehensively examines existing research into the preventive and therapeutic potential of tocotrienols in addressing age-related musculoskeletal issues. It sheds light on the promising role of tocotrienols in enhancing musculoskeletal health and overall wellbeing, emphasizing their significance within the broader context of age-related health concerns.

Platelet-rich plasma for pilonidal disease: a systematic review

OBJECTIVE

To examine the use of platelet-rich plasma (PRP) for treatment of pilonidal disease (PD) and thus provide a reference for clinical application.

METHODS

A systematic review of PubMed and the Cochrane Library was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. We considered all studies that reported the use of PRP for treatment of PD. Extracted data included the first author's name, year of publication, study type, number of included patients, inclusion and exclusion criteria, interventions, anesthesia, application of PRP (source, preparation, dose, and operation), antibiotics, follow-up time, therapeutic outcomes, and adverse events.

RESULTS

In total, eight randomized controlled trials and one prospective cohort study involving 809 patients were included. PRP reduced pain, accelerated healing, and reduced adverse events. The application of combined minimally invasive surgery achieved better results. However, overfilling of the wound with PRP in minimally invasive surgeries was shown to potentially increase the risk of adverse events.

CONCLUSION

PRP can be used as an adjuvant treatment in PD surgery to improve the therapeutic effect and reduce adverse events. The optimal combination of PRP and various factors is an important direction of future research.INPLASY registration number: INPLASY2023100070.

Treatment of dermal ulcer with autologous fibrin glue: Two case reports of an exploratory prospective pilot study

INTRODUCTION

The healing of recurrent and refractory skin ulcers requires a long time, during which there is risk of infection, and hospital admission is occasionally required for surgical or daily conservative treatment. Therefore, the development of promising treatments that promote faster, uneventful healing is a must. Composed of cryoprecipitate and thrombin, fibrin glue has a history of surgical use for preventing bleeding and spinal fluid leakage. Moreover, in-house cryoprecipitates contain higher concentrations of coagulation factors and cytokines that may enhance wound healing than commercially available products. However, the efficacy of completely autologous fibrin glue (AFG) in tissue repair has not yet been fully demonstrated.

PATIENT CONCERNS

This study aimed to evaluate the efficacy of AFG in the treatment of refractory skin ulcers in comparison with the conventional treatment.

DIAGNOSIS

Two patients with skin ulcer on their lower extremities due to trauma or scleroderma who showed resistance to conventional treatment were included in the study. Both study participants were diagnosed with refractory skin ulcer and were ineligible for autologous skin transplantation.

INTERVENTIONS

AFG was prepared following autologous blood donation using a Cryoseal® system. Subsequently, AFG was administered to 50% of the area of each ulcer and observed for 4 weeks in comparison with recombinant basic fibroblast growth factor with bucladesine sodium treatment that was administered to the rest of the ulcer.

OUTCOMES

The skin ulcer after trauma in participant 1 showed better improvement in the AFG-treated area. Although AFG did not show superiority regarding the ulcer area of a patient with scleroderma, it guarded the continuous exudation from the edge of the swollen skin surrounding the ulcer.

CONCLUSION

AFG showed effective and beneficial results for wound healing of refractory skin ulcer and prevented exudation without any severe adverse events.

A Comprehensive Review on Platelet-Rich Plasma Activation: A Key Player in Accelerating Skin Wound Healing

Platelet-rich plasma (PRP) activation is emerging as a promising and multifaceted tool for accelerating skin wound healing. This review extensively examines PRP's role in wound healing, focusing on its composition, mechanisms of action, activation methods, and clinical applications. PRP's potential to enhance both chronic and acute wound healing and its applications in cosmetic and aesthetic procedures are explored. Furthermore, this review investigates safety concerns, including adverse reactions, infection risks, and long-term safety implications. Looking to the future, emerging technologies, combination therapies, personalized medicine approaches, and regulatory developments are discussed, pointing towards an important and transformative era in wound healing and regenerative medicine. With its wide-ranging implications for healthcare, PRP activation has the potential to become a ubiquitous and essential therapeutic option, improving patient outcomes and reducing healthcare costs.

A Review of Cyclic Phosphatidic Acid and Other Potential Therapeutic Targets for Treating Osteoarthritis

Osteoarthritis (OA), a chronic degenerative joint disease, is the most common form of arthritis. OA occurs when the protective cartilage that cushions the ends of bones gradually breaks down. This leads to the rubbing of bones against each other, resulting in pain and stiffness. Cyclic phosphatidic acid (cPA) shows promise as a treatment for OA. In this article, we review the most recent findings regarding the biological functions of cPA signaling in mammalian systems, specifically in relation to OA. cPA is a naturally occurring phospholipid mediator with unique cyclic phosphate rings at the sn-2 and sn-3 positions in the glycerol backbone. cPA promotes various responses, including cell proliferation, migration, and survival. cPA possesses physiological activities that are distinct from those elicited by lysophosphatidic acid; however, its biochemical origin has rarely been studied. Although there is currently no cure for OA, advances in medical research may lead to new therapies or strategies in the future, and cPA has potential therapeutic applications.

Platelet-Rich Plasma Power-Mix Gel (ppm)-An Orthobiologic Optimization Protocol Rich in Growth Factors and Fibrin

Platelet- and fibrin-rich orthobiologic products, such as autologous platelet concentrates, have been extensively studied and appreciated for their beneficial effects on multiple conditions. Platelet-rich plasma (PRP) and its derivatives, including platelet-rich fibrin (PRF), have demonstrated encouraging outcomes in clinical and laboratory settings, particularly in the treatment of musculoskeletal disorders such as osteoarthritis (OA). Although PRP and PRF have distinct characteristics, they share similar properties. The relative abundance of platelets, peripheral blood cells, and molecular components in these orthobiologic products stimulates numerous biological pathways. These include inflammatory modulation, augmented neovascularization, and the delivery of pro-anabolic stimuli that regulate cell recruitment, proliferation, and differentiation. Furthermore, the fibrinolytic system, which is sometimes overlooked, plays a crucial role in musculoskeletal regenerative medicine by regulating proteolytic activity and promoting the recruitment of inflammatory cells and mesenchymal stem cells (MSCs) in areas of tissue regeneration, such as bone, cartilage, and muscle. PRP acts as a potent signaling agent; however, it diffuses easily, while the fibrin from PRF offers a durable scaffolding effect that promotes cell activity. The combination of fibrin with hyaluronic acid (HA), another well-studied orthobiologic product, has been shown to improve its scaffolding properties, leading to more robust fibrin polymerization. This supports cell survival, attachment, migration, and proliferation. Therefore, the administration of the "power mix" containing HA and autologous PRP + PRF may prove to be a safe and cost-effective approach in regenerative medicine.

Advances in Platelet-Rich Plasma Treatment for Spinal Diseases: A Systematic Review

Spinal diseases are commonly associated with pain and neurological symptoms, which negatively impact patients' quality of life. Platelet-rich plasma (PRP) is an autologous source of multiple growth factors and cytokines, with the potential to promote tissue regeneration. Recently, PRP has been widely used for the treatment of musculoskeletal diseases, including spinal diseases, in clinics. Given the increasing popularity of PRP therapy, this article examines the current literature for basic research and emerging clinical applications of this therapy for treating spinal diseases. First, we review in vitro and in vivo studies, evaluating the potential of PRP in repairing intervertebral disc degeneration, promoting bone union in spinal fusion surgeries, and aiding in neurological recovery from spinal cord injury. Second, we address the clinical applications of PRP in treating degenerative spinal disease, including its analgesic effect on low back pain and radicular pain, as well as accelerating bone union during spinal fusion surgery. Basic research demonstrates the promising regenerative potential of PRP, and clinical studies have reported on the safety and efficacy of PRP therapy for treating several spinal diseases. Nevertheless, further high-quality randomized controlled trials would be required to establish clinical evidence of PRP therapy.

Intrauterine Infusion of Leukocyte-Poor Platelet-Rich Plasma Is an Effective Therapeutic Protocol for Patients with Recurrent Implantation Failure: A Retrospective Cohort Study

BACKGROUND

The clinical application of autologous leukocyte-poor platelet-rich plasma (LP-PRP) in patients with recurrent implantation failure (RIF) is rare. This retrospective observational cohort study aimed to evaluate the efficacy of LP-PRP intrauterine infusion in patients with RIF.

METHODS

Patients with RIF undergoing frozen embryo transfer (FET) from January 2019 to December 2021 (n = 118) were enrolled, with those undergoing LP-PRP intrauterine infusion as the PRP group (n = 64), and those receiving no LP-PRP treatment as the control group (n = 54). The beta-human chorionic gonadotropin (β-hCG)-positive rate, clinical pregnancy rate (CPR), live birth rate (LBR), and miscarriage rate (MR) per ET cycle were compared.

RESULTS

The β-hCG-positive rate (57.8% vs. 38.9%, p = 0.041), CPR (45.3% vs. 24.5%, p = 0.022), and LBR per ET cycle (42.2% vs. 18.5%, p = 0.009) were higher in the PRP group than in the control group, and the three variables (62.5% vs. 41.2%, p = 0.040, 47.5% vs. 23.5%, p = 0.033, and 47.5% vs. 20.6%, p = 0.027) in the PRP group transferred with the blastocyst-stage embryos were also higher than those in the control group. The MR was similar in all groups.

CONCLUSIONS

The LP-PRP treatment could improve the β-hCG-positive rate, CPR, and LBR in RIF patients undergoing FET cycles.

State of the art in assisted reproductive technologies for patients with advanced maternal age

According to the World Health Organization, the female reproductive age lasts up to 49 years, but problems with the realization of women's reproductive rights may arise much earlier. Significant numbers of factors affect the state of reproductive health: socioeconomic, ecological, lifestyle features, the level of medical literacy, and the state of the organization and medical care quality. Among the reasons for fertility decline in advanced reproductive age are the loss of cellular receptors for gonadotropins, an increase in the threshold of sensitivity of the hypothalamic-pituitary system to the action of hormones and their metabolites, and many others. Furthermore, negative changes accumulate in the oocyte genome, reducing the possibility of fertilization, normal development and implantation of the embryo and healthy offspring birth. Another theory of ageing causing changes in oocytes is the mitochondrial free radical theory of ageing. Taking into account all these age-related changes in gametogenesis, this review considers modern technologies aimed at the preservation and realization of female fertility. Among the existing approaches, two main ones can be distinguished: methods allowing the preservation of reproductive cells at a younger age using ART intervention and cryobanking, as well as methods aimed at improving the basic functional state of advanced-age women's oocytes and embryos.

Personalized regenerative strategies and molecular diagnosis for in vitro fertilization success: a case report

Limited options are available for infertility associated with damaged or suboptimal tissues, typically the endometrium or ovaries. The goal of regenerative medicine is to restore function to specific tissues. Here, a 35-year-old female patient underwent two interventions of regenerative medicine: (i) autologous mesenchymal stem cells (MSCs) were applied in the myometrium, and (ii) intraovarian infusion of platelet-rich plasma (PRP). After two failed in vitro fertilization cycles (IVF), in which the endometrium was <5 mm, MSCs were applied, achieving a 7 mm trilaminar lining; however, the embryo quality remained poor. Therefore, intraovarian PRP was utilized for the next IVF cycle; the patient's response improved, and a euploid embryo developed. After the embryo transfer and a normal 38 weeks of pregnancy, a baby girl was born. Here, we demonstrate two forms of regenerative medicine that can be utilized to improve IVF.

Autologous Platelet and Extracellular Vesicle-Rich Plasma as Therapeutic Fluid: A Review

The preparation of autologous platelet and extracellular vesicle-rich plasma (PVRP) has been explored in many medical fields with the aim to benefit from its healing potential. In parallel, efforts are being invested to understand the function and dynamics of PVRP that is complex in its composition and interactions. Some clinical evidence reveals beneficial effects of PVRP, while some report that there were no effects. To optimize the preparation methods, functions and mechanisms of PVRP, its constituents should be better understood. With the intention to promote further studies of autologous therapeutic PVRP, we performed a review on some topics regarding PVRP composition, harvesting, assessment and preservation, and also on clinical experience following PVRP application in humans and animals. Besides the acknowledged actions of platelets, leukocytes and different molecules, we focus on extracellular vesicles that were found abundant in PVRP.

Evolution and Clinical Advances of Platelet-Rich Fibrin in Musculoskeletal Regeneration

Over the past few decades, various forms of platelet concentrates have evolved with significant clinical utility. The newer generation products, including leukocyte-platelet-rich fibrin (L-PRF) and advanced platelet-rich fibrin (A-PRF), have shown superior biological properties in musculoskeletal regeneration than the first-generation concentrates, such as platelet-rich plasma (PRP) and plasma rich in growth factors. These newer platelet concentrates have a complete matrix of physiological fibrin that acts as a scaffold with a three-dimensional (3D) architecture. Further, it facilitates intercellular signaling and migration, thereby promoting angiogenic, chondrogenic, and osteogenic activities. A-PRF with higher leukocyte inclusion possesses antimicrobial activity than the first generations. Due to the presence of enormous amounts of growth factors and anti-inflammatory cytokines that are released, A-PRF has the potential to replicate the various physiological and immunological factors of wound healing. In addition, there are more neutrophils, monocytes, and macrophages, all of which secrete essential chemotactic molecules. As a result, both L-PRF and A-PRF are used in the management of musculoskeletal conditions, such as chondral injuries, tendinopathies, tissue regeneration, and other sports-related injuries. In addition to this, its applications have been expanded to include the fields of reconstructive cosmetic surgery, wound healing in diabetic patients, and maxillofacial surgeries.

Intra-ovarian infusion of autologous platelet-rich plasma in women with poor ovarian reserve: A before and after study

OBJECTIVE

Female ovarian reserve progressively declines with increasing age. Intraovarian injection of platelet-rich plasma (PRP) seems to be an alternative treatment to increase fertility in women. Therefore, this study aimed to evaluate the effect of intra-ovarian infusion of PRP in treating women with poor ovarian reserve.

MATERIALS AND METHODS

In this before-and-after study, 22 infertile women with a poor ovarian reserve who underwent in vitro fertilization with the GnRH antagonist protocol were enrolled. After the oocyte retrieval undergoing vaginal ultrasound guide, PRP was injected into the ovary with a puncture needle under general anesthesia. Finally, the levels of anti-Müllerian hormone (AMH) and antral follicle counts (AFCs) were compared in all participants before and three months after the PRP injection.

RESULTS

Our findings showed that AMH significantly increased after the intra-ovarian infusion of PRP (P < 0.001) in these women, while no significant changes were observed in AFC (P = 0.140) at the end of the study. In addition, logistic regression indicated that body mass index (BMI) and maternal age had no significant effect on ovarian response to PRP injection. However, the duration of infertility > 5 years was associated with a 20-fold increase in the probability of AFC < 7 in women with poor ovarian reserve.

CONCLUSIONS

PRP can increase the chance of fertility in women with poor ovarian reserve by significantly increasing AMH levels.

Effect of intra-ovarian platelet rich plasma in women with poor ovarian response

Background

Poor ovarian responder (POR) women, whose ovarian response to gonadotropin stimulation has decreased, are at higher risk of unsuccessful in-vitro fertilization (IVF). Therefore, this study designed to evaluate the effect of intra-ovarian platelet rich plasma (PRP) on POR women.

Methods

This single-arm trial research was done on 20 POR women referred to the IVF Unit, university-based hospital, Tehran, Iran between October 2020 and September 2021. For all participants, autologous PRP was injected into each ovary by transvaginal ultrasound guidance under spinal anesthesia between days 12 and 14 of the menstrual cycle. After 12 weeks of PRP injection, embryo transfers were carried out following our routine IVF department protocol. The study outcomes were the number of mature oocytes, and pregnancy rates.

Results

The average age of the participants was 41.80±1.82 yr. The average infertility duration was 9.70±1.89 yrs., with 80% primary infertility type. After PRP injection, follicle-stimulating hormone levels dropped about 1% (P=0.499), anti-Mullerian hormone levels were on average 4.5% higher (P=0.356), and estradiol levels raised by 1.2% (P=0.681). The average number of oocytes and their quality increased after PRP injection, while these changes were not significant (p-value>0.05). Chemical pregnancy was detected in 3 (15%) women and clinical pregnancy was detected only in one person.

Conclusion

This study revealed that PRP injection into ovaries of POR women is safe and had a tendency to improve ovarian reserve markers and serum levels of AMH, estradiol, number and quality of oocytes.

Combined subchondral and intra-articular injections of bone marrow aspirate concentrate provide stable results up to 24 months

PURPOSE

The aim of this study was to evaluate the clinical and imaging findings up to 24 months of follow-up in patients treated with combined subchondral and intra-articular bone marrow aspirate concentrate (BMAC) injections for the treatment of knee osteoarthritis (OA).

METHODS

Thirty consecutive patients (19 males, 11 females) aged between 40 and 75 years (mean age 56.4 ± 8.1 years) with unilateral symptomatic knee OA (Kellgren-Lawrence 2-3) were included in the study. Patients were treated with combined intra-articular and subchondral bone BMAC injections (total 9 ml) under fluoroscopic control. IKDC subjective score, VAS for pain, KOOS, and EQ-VAS were prospectively evaluated up to 24 months. Radiographs were performed at baseline and at 24 months after the procedure. MRI was evaluated with the WORMS score at baseline, 6-12 months, and 24 months of follow-up. The statistical analysis was performed using SPSS v.19.0 and for all tests p < 0.05 was considered significant.

RESULTS

No major complications and a 13% failure rate were reported. The IKDC subjective score remained stable from 62.6 ± 19.4 at 12 months to 63.4 ± 17.1 at 24 months (both p < 0.0005 compared to baseline, 40.5 ± 12.5). Similar improvements were reported for all KOOS subscales, while EQ-VAS did not report any significant improvement. VAS pain worsened from 3.0 ± 1.9 at 12 months to 4.4 ± 1.8 at the final follow-up (p = 0.0001), although remaining lower compared to the baseline value of 6.3 ± 1.8 (p = 0.002). The radiographic evaluation did not reveal signs of improvement or deterioration of the OA grade. The MRI findings showed a worsening in marginal osteophytes and synovitis, but a significant reduction of bone marrow edema at 24 months (p < 0.0005).

CONCLUSION

Combined intra-articular and subchondral BMAC injections provided clinical and imaging benefits up to 24 months for the treatment of symptomatic knee OA, with durable clinical results, a low failure rate, and a significant reduction of bone marrow edema.

Variability in Platelet-Rich Plasma Preparations Used in Regenerative Medicine: A Comparative Analysis

BACKGROUND

Platelet-rich plasma (PRP) and its derivatives are used in several aesthetic, dental, and musculoskeletal procedures. Their efficacy is primarily due to the release of various growth factors (GF), interleukins, cytokines, and white blood cells. However, the PRP preparation methods are highly variable, and studies lack consistency in reporting complete procedures to prepare PRP and characterize PRP and its derivatives. Also, all the tissue-specific (in vivo and in vitro) interactions and functional properties of the various derivatives/factors of the PRP have not been taken into consideration by any study so far. This creates a potential space for further standardization of the PRP preparation methods and customization of PRP/PRP derivatives targeted at tissue-specific/pathology specific requirements that would enable efficacious and widely acceptable usage of PRP as main therapy, rather than being used as adjuvant therapy. The main objective of our study was to investigate the variability in PRP preparation methods and to analyze their efficacy and reliability.

METHOD

This study considered articles published in the last 5 years, highlighting the variability in their PRP preparation methods and characterization of PRP. Following the PRISMA protocol, we selected 13 articles for the study. The selected articles were assessed using NHLBI quality assessment tool.

RESULTS

We noted differences in (1) approaches to producing PRP, (2) extent of characterization of PRP, (3) small scale and large-scale preparation methods, (4) in vitro and in vivo studies.

CONCLUSION

We identified two studies describing the procedures which are simple, reproducible, economical, provide a good yield of platelets, and therefore can be considered methods for further tissue-specific and pathology-specific standardizations of PRP and its derivatives. We recommend further randomized studies to understand the full therapeutic potential of the constituents of PRP and its derivatives.

Role of adipose tissue grafting and adipose-derived stem cells in peripheral nerve surgery

The application of autologous fat grafting in reconstructive surgery is commonly used to improve functional form. This review aims to provide an overview of the scientific evidence on the biology of adipose tissue, the role of adipose-derived stem cells, and the indications of adipose tissue grafting in peripheral nerve surgery. Adipose tissue is easily accessible through the lower abdomen and inner thighs. Non-vascularized adipose tissue grafting does not support oxidative and ischemic stress, resulting in variable survival of adipocytes within the first 24 hours. Enrichment of adipose tissue with a stromal vascular fraction is purported to increase the number of adipose-derived stem cells and is postulated to augment the long-term stability of adipose tissue grafts. Basic science nerve research suggests an increase in nerve regeneration and nerve revascularization, and a decrease in nerve fibrosis after the addition of adipose-derived stem cells or adipose tissue. In clinical studies, the use of autologous lipofilling is mostly applied to secondary carpal tunnel release revisions with promising results. Since the use of adipose-derived stem cells in peripheral nerve reconstruction is relatively new, more studies are needed to explore safety and long-term effects on peripheral nerve regeneration. The Food and Drug Administration stipulates that adipose-derived stem cell transplantation should be minimally manipulated, enzyme-free, and used in the same surgical procedure, e.g. adipose tissue grafts that contain native adipose-derived stem cells or stromal vascular fraction. Future research may be shifted towards the use of tissue-engineered adipose tissue to create a supportive microenvironment for autologous graft survival. Shelf-ready alternatives could be enhanced with adipose-derived stem cells or growth factors and eliminate the need for adipose tissue harvest.

Full Diabetic Foot Ulcer Healing and Pain Relief Based on Platelet-Rich-Plasma gel Formulation Treatment and the Involved Pathways

Diabetic foot ulcer is a severe Diabetic Mellitus-associated complication. It is induced by poor glycemic control, which leads to peripheral neuropathy and vascular diseases. Platelet-rich plasma could be beneficial for healing processes due to its active biomolecules that promotes immunomodulation, angiogenesis, cell proliferation and analgesia.

Hamizul MHA, Khairul Bariah AAN, Wan Kamarul Zaman WS, Nordin F. Regenerative Medicine Therapy in Malaysia: An Update

Regenerative medicine is a field in medicine that relates to the ability to correct congenital anomalies and to repair or replace tissues and organs that have been destroyed by age, disease, or trauma. To date, promising preclinical and clinical data supported the possibility of using regenerative medicine to treat both chronic diseases and acute insults, as well as maladies affecting a wide range of organ systems and contexts, such as dermal wounds, cardiovascular diseases and traumas, cancer treatments, and more. One of the regenerative medicine therapies that have been used widely is stem cells. Stem cells, especially mesenchymal and hematopoietic stem cells, play an important role in treating chronic diseases, such as leukemia, bone marrow, autoimmune disease, and urinary problems. Despite considerable advancements in stem cell biology, their applications are limited by ethical concerns about embryonic stem cells, tumor development, and rejection. Nevertheless, many of these constraints, are being overcome, which could lead to significant advancements in disease management. This review discusses the current developments and advancements of regenerative medicine therapy (RMT) advancements in Malaysia compared to other Asian countries. The limitations in the application of RMT are also highlighted.

Influence of Sexual Dimorphism, Aging, and Differential Cell Capture Efficiency of Blood Separation Systems on the Quality of Platelet-Rich Plasma

Few studies have checked the impact of the hormonal/immunological dimorphism of patients on the cellular composition of platelet-rich plasma products (PRP). Whole blood (WB) from 26 volunteers was concentrated using a device previously characterized. Platelet and white blood cell (WBC) counts in WB and PRP were compared between genders, and after the population was split into pre (≤50 years)- and post (>50 years)-menopausal ages. In WB, platelet−total WBC densities were comparable in men and women. The phagocytic cell composition differed (p ≤ 0.04). After dividing by ages, phagocytic cell discrepancies were linked to women > 50 years (p ≤ 0.05), and differences emerged in lymphocyte counts (lower in >50 years groups, within and between genders, p ≤ 0.05). In PRP, densities were significantly higher, but the PRP/WB ratios varied according to blood cell (lower for phagocytic cells) and between subjects (more favorable at a lower density of a particular blood cell in WB). This “system compensatory efficiency” reduced/reverted PRP differences in the leukocyte composition between genders/age−sex groups in WB. In PRP, neutrophils were higher in younger men than older women (p < 0.05). WB lymphocyte differences between age−sex groups persisted. Age is a more determining factor than sex in the preparation of PRP. Post-menopause, sexual dimorphism strongly influences the composition of leukocytes, also conditioned by the capture efficiency of the system.

Mesenchymal Stem Cells and PRP Therapy Favorize Leak Closure After Sleeve Gastrectomy in Zucker Rats

INTRODUCTION

Sleeve gastrectomy (SG) is the most performed bariatric surgery but gastric leaks following SG occur in up to 2% of cases. Regenerative medicine is emerging as a promising field offering multiple possibilities in wound healing. We studied the efficiency of locally administered mesenchymal stem cells (MSCs) and platelet-rich plasma (PRP) on leak closure following SG in rats.

METHODS

The amount of PRP and MSCs extracted from one rat was analyzed and a model of gastric leak was developed in 10-week-old male Zucker rats. Twenty-four rats underwent SG fashioned with a leak. After 24 h, a second surgery was performed. The control group was treated by peritoneal lavage and drainage only while the experimental group received an additional treatment of locally administered MSCs and PRP at the leak orifice. Analysis of the leak healing process was done by an anatomopathological examination of the stomach 1, 2, 3, and 4 weeks after SG.

RESULTS

The extraction of MSCs and PRP from one rat was necessary for three recipients. Anatomopathological examination suggests that the closure of the leak orifice was faster in the experimental group. Statistical analysis revealed a significantly increased mucosae renewal and fibrosis score at the leak orifice after treatment with MSCs and PRP (p < 0.001).

CONCLUSION

These results suggest that PRP and MSCs may accelerate the closure of leaks following SG in rats and may become a new tool in the treatment of human gastric leaks but more research on this topic is needed to confirm these findings.

Intraovarian Injection of Autologous Platelet-Rich Plasma Improves Therapeutic Approaches in The Patients with Poor Ovarian Response: A Before-After Study

BACKGROUND

Advanced age is associated with a decline in the natural oocytes, low oocyte yield, and also increases the assisted reproductive technology (ART) failure rate, and consequently resulted in a pregnancy rate decrease. Platelet-rich plasma (PRP) is one of the proposed therapeutic strategies for women with poor ovarian response (POR). Because of the autologous source of PRP, the lowest risks of disease transmission, immunogenic and allergic reactions have been expected. This study aimed to evaluate the single-dose intraovarian injection of autologous PRP in poor ovarian reserve.

MATERIALS AND METHODS

We conducted a clinical trial study in the Al-Zahra hospital and Milad Infertility Clinic, Tabriz, Iran (April and May, 2021). A total of thirty-five women with a POR and mean age 40.68 ± 0.34 enrolled in this study. After injection of autologous PRP into the ovaries, the number of oocytes, antral follicles, and level of estradiol, anti-Müllerian hormone (AMH), follicle-stimulating hormone (FSH), luteal hormone (LH), FSH/LH ratio also were evaluated while, these parameters were evaluated before PRP administration.

RESULTS

At the 2-month follow-up, women treated with PRP showed a significant elevation in the number of oocytes (3.68 ± 0.24, P=0.0043) and embryos (3.17 ± 0.14, P=0.0001), as well as in the estradiol levels (404.1 ± 16.76 vs. 237.7 ± 13.14, P=0.0003).

CONCLUSION

Single PRP injection is effective and might be a promising therapeutic approach in the patients with POR to conceive with their own oocytes, although further evidence is required to assess the influence of PRP on the live birth rate.

Clinical management of alveolar osteitis. A systematic review

Background

Alveolar Osteitis (AO) is one of the most common complications of tooth extraction. Several therapeutic interventions have been described for the treatment of AO, however, there are no treatment standardized protocols. The aim of this study was to conduct a systematic review on the efficacy in pain control of the different treatments for AO. The feasibility of the application of these interventions is also discussed.

Material and Methods

A structured electronic and hand search strategy was applied to PubMed, Scopus, Cochrane Library, OpenGrey, and Google Scholar between January 2010 and July 2020 to identify studies according to PRISMA guidelines. The inclusion criteria were original English and Spanish clinical trials that analyzed pain-control parameters according to visual analog scale (VAS, 0-10 scale), or pain relief patients’ percentages. Those treatments that reach VAS ≤ 4 on day 2 or before; or ≥ 85% of patients with absence of pain symptoms at day 7 or before were considered accepTable for their recommendation.

Results

The final review included 17 clinical trials. Among them, there were analyzed a total of 39 different AO treatments. 53,8% of the treatments fulfill the proposed parameters for pain control.

Conclusions

Treatment alternatives are multiple, heterogeneous, and difficult to compare. The management of AO is summarized in basic (intra-alveolar irrigation) and specific procedures (Alveogyl®, Neocones®, SaliCept Patch®, Low-Level Laser, Platelet-Rich Fibrin) that reach pain control success. They could be selected according to their availability and advantages or disadvantages.

Key words:Dry socket, alveolar osteitis, treatment, management, pain control, pain relief.

Intraosseous Injections Are Safe And Effective in Knee Osteoarthritis: A Systematic Review

Purpose

To evaluate clinical outcomes after intraosseous injection for knee osteoarthritis systematically with available clinical evidence.

Methods

A systematic search methodology of the PUBMED, EMBASE, and CINAHL databases was conducted in November 2020. The search workflow was in adherence to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). The following inclusion criteria were adopted: clinical trials of any level of evidence, reporting clinical outcomes following intraosseous injections of bone substitutes or biologic agents, and mesenchymal stem cells or platelet-rich plasma into the knee as treatment modalities for osteoarthritis. Duplicate data and articles not written in English were excluded from this review.

Results

Six studies were identified and included in this review, with a total of 167 patients. Two studies used subchondroplasty CaP injections, while 4 studies used intraosseous injections of platelet-rich plasma. Two studies provided Level II evidence, 2 studies provided Level III evidence, and a further 2 provided Level IV evidence. Five out of 6 studies reported data using the visual analog scale, 4 studies used the Knee Injury and Osteoarthritis Outcome Score, while 3 studies used the Western Ontario and McMaster Universities Osteoarthritis Index. Clinical improvements in pain and functionality were documented in all trials, with only a few patients experiencing adverse events.

Conclusion

Intraosseous injections for knee osteoarthritis are safe and effective. However, multiple pertinent variables such as safety, cost of treatment, and performance against placebos and other treatment modalities require further evaluation before intraosseous injections can be considered as standard treatment for patients presenting with osteoarthritis of the knee.

Improved wound healing of diabetic foot ulcers using human placenta-derived mesenchymal stem cells in gelatin electrospun nanofibrous scaffolds plus a platelet-rich plasma gel: A randomized clinical trial

AIM

The effectiveness of nanofibers containing human placenta-derived mesenchymal stem cells (hPDMSCs) plus platelet-rich plasma (PRP) for healing of diabetic foot ulcers (DFUs) was investigated.

METHODS

hPDMSCs were isolated from human donor placentas, and cultured in electrospun gelatin nanofibrous scaffolds (GNS). Twenty-eight patients with DFUs were randomized into three groups in a 12-week trial: (A) Treated with hPDMSCs; (B) Treated with hPDMSCs after coating the ulcer with PRP gel; (C) Control group received standard wound care. Wound area and pain freewalkingdistance were measured every 2 weeks.

RESULTS

Flow cytometry showed the expression of mesenchymal markers. SEM images and DAPI staining indicated significantly higher levels of hPDMSC proliferation on GNS after 3 and 7 days of culture. The MTS assay showed a significant increase in proliferation on GNS, compared to controls. Wound size reduction was 66% in group A, 71% in group B, and 36% in control group C. A significant difference in wound closure and pain-free walking distance was observed between groups A and B, compared to control group C (p < 0.05), but no difference between groups A and B. Biopsy of the implanted tissue showed the development of new capillary formation in groups A and B.

CONCLUSION

Implantation of hPDMSCs in GNS accelerated wound healing and improved clinical parameters in DFU patients.

Bone Morphogenetic Protein 7 Expression in Alveolar Bone Addition With Autologous Blood, Lyophilized Bone and Atelocollagen

BACKGROUND/AIM

The biomaterials used in guided bone regeneration have undergone significant diversification in recent years. This study aimed to evaluate alveolar bone addition and bone morphogenetic protein 7 (BMP7) expression using an improved autologous and xenogeneic biomaterial.

MATERIALS AND METHODS

Chronic marginal periodontitis was induced in sheep; the intervention group received bone addition as periodontal therapy, using a composite system with lyophilized bovine bone enriched with atelocollagen type 1, platelet-rich plasma and advanced platelet-rich fibrin (A-PRF). Six weeks after the intervention, the dentoalveolar structures were evaluated using hematoxylin-eosin and immunohistochemical staining, to evaluate bone addition and BMP7 expression.

RESULTS

The untreated sheep showed inflammation, periodontal ligament destruction, remnants of calculus and bacterial plaque as well as foreign bodies in the desmodontal space, without sings of repair. In the treated sheep, fibroblasts/fibrosis, cartilage and/or new bone, cellular cementum and desmodontium, along with remnants of biomaterial with various degrees of cellularity were observed. In the untreated group, the presence of BMP7 was found in osteoblasts and osteocytes while in the treated group, it was mainly found in the biomaterial remnants, while immunohistochemical staining was less intense in the newly formed osteo-periodontal tissues. Quantitative analysis using the Mann-Whitney U-test showed highly statistically significant differences between the two groups, demonstrating the efficiency of this composite system.

CONCLUSION

The current composite system meets all the necessary conditions for promising guided alveolar bone regeneration.

The Effect of Platelet-Rich Plasma on the Intra-Articular Microenvironment in Knee Osteoarthritis

Knee osteoarthritis (KOA) represents a clinical challenge due to poor potential for spontaneous healing of cartilage lesions. Several treatment options are available for KOA, including oral nonsteroidal anti-inflammatory drugs, physical therapy, braces, activity modification, and finally operative treatment. Intra-articular (IA) injections are usually used when the non-operative treatment is not effective, and when the surgery is not yet indicated. More and more studies suggesting that IA injections are as or even more efficient and safe than NSAIDs. Recently, research to improve intra-articular homeostasis has focused on biologic adjuncts, such as platelet-rich plasma (PRP). The catabolic and inflammatory intra-articular processes that exists in knee osteoarthritis (KOA) may be influenced by the administration of PRP and its derivatives. PRP can induce a regenerative response and lead to the improvement of metabolic functions of damaged structures. However, the positive effect on chondrogenesis and proliferation of mesenchymal stem cells (MSC) is still highly controversial. Recommendations from in vitro and animal research often lead to different clinical outcomes because it is difficult to translate non-clinical study outcomes and methodology recommendations to human clinical treatment protocols. In recent years, significant progress has been made in understanding the mechanism of PRP action. In this review, we will discuss mechanisms related to inflammation and chondrogenesis in cartilage repair and regenerative processes after PRP administration in in vitro and animal studies. Furthermore, we review clinical trials of PRP efficiency in changing the OA biomarkers in knee joint.

Synergistic Effect of Biomaterial and Stem Cell for Skin Tissue Engineering in Cutaneous Wound Healing: A Concise Review

Skin tissue engineering has made remarkable progress in wound healing treatment with the advent of newer fabrication strategies using natural/synthetic polymers and stem cells. Stem cell therapy is used to treat a wide range of injuries and degenerative diseases of the skin. Nevertheless, many related studies demonstrated modest improvement in organ functions due to the low survival rate of transplanted cells at the targeted injured area. Thus, incorporating stem cells into biomaterial offer niches to transplanted stem cells, enhancing their delivery and therapeutic effects. Currently, through the skin tissue engineering approach, many attempts have employed biomaterials as a platform to improve the engraftment of implanted cells and facilitate the function of exogenous cells by mimicking the tissue microenvironment. This review aims to identify the limitations of stem cell therapy in wound healing treatment and potentially highlight how the use of various biomaterials can enhance the therapeutic efficiency of stem cells in tissue regeneration post-implantation. Moreover, the review discusses the combined effects of stem cells and biomaterials in in vitro and in vivo settings followed by identifying the key factors contributing to the treatment outcomes. Apart from stem cells and biomaterials, the role of growth factors and other cellular substitutes used in effective wound healing treatment has been mentioned. In conclusion, the synergistic effect of biomaterials and stem cells provided significant effectiveness in therapeutic outcomes mainly in wound healing improvement.

Effects of Intraovarian Injection of Autologous Platelet-Rich Plasma on Ovarian Rejuvenation in Poor Responders and Women with Primary Ovarian Insufficiency

Injection of intraovarian platelet-rich plasma (PRP) was recently presented in terms of improvement ovarian function in women with a poor ovarian response (POR) or primary ovarian insufficiency (POI). In a before and after study, 17 poor responder women and 9 women with the diagnosis of POI were recruited. The multifocal intramedullary infusion of 1.5 ml activated PRP was performed into each ovary. The majority of women in both groups received the second PRP injection with the twofold increase in the dosage to 3ml, 3 months after the first injection. Evaluation of serum anti-mullerian hormone ( AMH), follicle-stimulating hormone (FSH), luteinizing hormone (LH), and estradiol (E2) was performed. In addition, all women were followed with regard to pregnancy outcome up to delivery. In the POI group, menstrual restoration was monitored. The significant difference was not detected regarding the hormonal profile between the three time points in both groups. With regard to pregnancy outcome, 8/17 (47%) of PORs had spontaneous pregnancy in response to PRP injection. Of those, three women (37.55%) had abortions, whereas 4 pregnancies (50%) led to healthy live births, and one woman (12.5%) was in the 24^th week of her pregnancy. Menstruation recovery occurred among 22.2% of women with POI after the second PRP injection, but no one became pregnant. Intraovarian injection of autologous PRP might be considered an alternative treatment in poor responders. As for women with POI, it is questionable whether PRP could induce menstrual recovery.

Peripheral Nerve Regeneration Using a Cytokine Cocktail Secreted by Skeletal Muscle-Derived Stem Cells in a Mouse Model

Severe peripheral nerve injury, which does not promise natural healing, inevitably requires clinical treatment. Here, we demonstrated the facilitation effect of peripheral nerve regeneration using a cytokine cocktail secreted by skeletal muscle-derived stem cells (Sk-MSCs). Mouse sciatic nerve was transected with a 6 mm gap and bridged collagen tube, and the culture supernatant of Sk-MSCs with 20% adult mouse serum (AMS)/Iscove’s modified Dulbecco’s medium (IMDM) was administered into the tube immediately after the operation, followed by an injection once a week for six weeks through the skin to the surrounding tube of the cytokine (CT) group. Similarly, 20% AMS/IMDM without cytokines was administered to the non-cytokine control (NT) group. Tension recovery in the plantar flexor muscles via electrical stimulation at the upper portion of the damaged nerve site, as well as the numerical recovery of axons and myelinated fibers at the damaged site, were evaluated as an index of nerve regeneration. Specific cytokines secreted by Sk-MSCs were compared with damaged sciatic nerve-derived cytokines. Six weeks after operation, significantly higher tension output and numerical recovery of the axon and myelinated fibers were consistently observed in the CT group, showing that the present cytokine cocktail may be a useful nerve regeneration acceleration agent. We also determined 17 candidate factors, which are likely included in the cocktail.

Evidence-based indications of platelet-rich plasma therapy

Introduction: Platelet-rich plasma (PRP) is an autologous blood-derived product that contains platelet concentrations at least 2/3 times above the normal level and includes platelet-related growth factors. The concept of PRP began in the 1970s in the field of hematology to treat patients with thrombocytopenia. In the 1980s and 1990s, PRP began to be used in surgical procedures such as maxillofacial surgery and plastic surgery. Since then, PRP had been used in orthopedic procedures, cardiac surgery, sports injuries, plastic surgery, gynecology, urology, and more recently in medical esthetics. Areas covered: This review analyzes the mechanisms of action, current indications, clinical evidence, safety and future directions of PRP in the management of various medical conditions. The literature search methodology included using medical subject headings terms to search in PubMed. Articles used were screened and critically appraised by the coauthors of this review. Expert Opinion: Platelet-rich plasma is a therapeutic option used to treat many medical conditions. PRP could be used alone or in combination with other procedures. The effectiveness and safety of PRP has been demonstrated in many medical scenarios, however there is limited availability of large randomized clinical trials.

A Systematic Review Evaluating the Efficacy of Intra-Ovarian Infusion of Autologous Platelet-Rich Plasma in Patients With Poor Ovarian Reserve or Ovarian Insufficiency

The emergence of autologous platelet-rich plasma (PRP) therapy reflects a break-through for infertile patients with premature ovarian failure. To study the efficacy of intra-ovarian infusion of autologous PRP on the improvement of ovarian reserve parameters and the subsequent artificial reproductive technique (ART) cycle outcomes in infertile women with poor ovarian reserve or premature ovarian insufficiency, a systematic search in electronic databases like Medline (through PubMed), Embase, Scopus, Web of Science, and Cochrane was done using relevant search terms. Except for case series, case reports, and review articles, all other types of studies, those evaluated for the effects of intra-ovarian infusion of PRP in subfertile women for decreased ovarian reserve (DOR) or premature ovarian insufficiency (POI) were included in our systematic review. The data were extracted from each eligible study and cross-checked by two authors. Intra-ovarian PRP infusion appears to be effective in ovarian rejuvenation, and the results of the subsequent intracytoplasmic sperm injection (ICSI) cycle are encouraging. PRP intervention was found to be beneficial in terms of an improvement in ovarian reserve parameters (increase in serum anti-mullerian hormone or antral follicle count or decrease in serum follicular stimulating hormone). ICSI cycle performance in terms of the total number of oocytes retrieved, number of two-pronuclei embryos, fertilization rate, number of cleavage stage embryos, number of good quality embryos, and cycle cancellation rate were found to be improved after intra-ovarian PRP infusion as compared to their previous cycle without PRP infusion.

Enhanced In Vivo Vascularization of 3D-Printed Cell Encapsulation Device Using Platelet-Rich Plasma and Mesenchymal Stem Cells

The current standard for cell encapsulation platforms is enveloping cells in semipermeable membranes that physically isolate transplanted cells from the host while allowing for oxygen and nutrient diffusion. However, long-term viability and function of encapsulated cells are compromised by insufficient oxygen and nutrient supply to the graft. To address this need, a strategy to achieve enhanced vascularization of a 3D-printed, polymeric cell encapsulation platform using platelet-rich plasma (PRP) and mesenchymal stem cells (MSCs) is investigated. The study is conducted in rats and, for clinical translation relevance, in nonhuman primates (NHP). Devices filled with PRP, MSCs, or vehicle hydrogel are subcutaneously implanted in rats and NHP and the amount and maturity of penetrating blood vessels assessed via histopathological analysis. In rats, MSCs drive the strongest angiogenic response at early time points, with the highest vessel density and endothelial nitric oxide synthase (eNOS) expression. In NHP, PRP and MSCs result in similar vessel densities but incorporation of PRP ensues higher levels of eNOS expression. Overall, enrichment with PRP and MSCs yields extensive, mature vascularization of subcutaneous cell encapsulation devices. It is postulated that the individual properties of PRP and MSCs can be leveraged in a synergistic approach for maximal vascularization of cell encapsulation platforms.

Washed Equine Platelet Extract as an Anti-Inflammatory Biologic Pharmaceutical

Mammalian platelets participate in the immediate tissue injury response by initiating coagulation and further promoting tissue injury mitigation and repair. The latter properties are deployed following platelet release of presynthetized morphogens, cytokines, and growth and chemotactic factors, which launch a tissue regenerative, angiogenic, and anti-inflammatory program. Several blood-derived biologic products, like platelet-rich plasma (PRP) and platelet lysate (PL), are currently on the market to allow proper healing and tissue regeneration. However, not all growth factors are released from the platelets and the final products contain plasma proteins such as albumin, fibrinogen, complement, and immunoglobulins, increasing the risks of serum sickness or allergic reaction. To address this problem, we developed a new platelet extract where equine blood platelets are concentrated, washed, and thereafter lysed by detergent Triton X-114. Distinct from PRP, this extract is devoid of albumin, fibrinogen, and immunoglobulins and is 266-fold enriched in platelet-derived growth factor content relative to PRP. Washed equine platelet extract (WEPLEX) is amenable to lyophilization without loss of biological activity. In vitro, WEPLEX significantly inhibits human and equine T cell proliferative response to phytohemagglutinin and also polarizes murine CD45⁺/CD11b⁺ peritoneal macrophages to an IL-10⁺ M2-like phenotype. In vivo, WEPLEX substantially improves clinical outcome of murine experimental dextran sulfate sodium colitis. We propose that equine-sourced, zoonosis-free WEPLEX may serve as an anti-inflammatory biological therapy across mammalian species.

Platelet-rich plasma another add-on treatment getting out of hand? How can clinicians preserve the best interest of their patients?

Add-on treatments in IVF are utilized to a great extent but without sufficient evidence showing their effectiveness. Since the offered treatments are usually costly and may be associated with yet unknown risks, this practice is not in the best interest of couples that may go to great lengths to conceive and have an offspring carrying their own genetic make-up. A recent addition to this armamentarium is the administration of platelet-rich plasma (PRP) in women with diminished ovarian reserve, implantation failures, and a thin endometrium. The only evidence for PRP comes from small scale and mostly before and after studies with clinically irrelevant end points. PRP has not been subjected to a rigorous clinical trial. It is a typical example of an add-on gaining widespread popularity based on biological plausibility and mind-bending theoretical presumptions. We should be extremely cautious prior to implementing PRP on a widescale and await the results of well-designed studies.

Intra-ovarian injection of platelet-rich plasma into ovarian tissue promoted rejuvenation in the rat model of premature ovarian insufficiency and restored ovulation rate via angiogenesis modulation

Premature Ovarian Insufficiency (POI) is viewed as a type of infertility in which the menopausal status occurs before the physiological age. Several therapeutic strategies have been introduced in clinic for POI treatment, although the outputs are not fully convincing. Platelet-rich plasma (PRP) is a unique blood product widely applied in regenerative medicine, which is based on the releasing of the growth factors present in platelets α-granules. In the current investigation, we examined the effectiveness of PRP as a therapeutic alternative for POI animals. POI in Wistar albino rats was induced by daily intraperitoneal (IP) administration of gonadotoxic chemical agent, 4-vinylcyclohexene dioxide (VCD) (160 mg/ kg) for 15 consecutive days. After POI induction, the PRP solution was directly injected intra-ovarian in two concentrations via a surgical intervention. Every two weeks post-injection, pathological changes were monitored in the ovaries using Hematoxylin-Eosin staining method, until eight weeks. Follicle Stimulating Hormone (FSH) content in serum was measured, together with the expression of the angiogenic-related transcripts ANGPT2 and KDR by real-time qPCR. Furthermore the fertility status of the treated rats was evaluated by mating trials. Histopathological examination revealed successful POI induction via the depletion of morphologically normal follicles in rats following VCD treatment compared to the control rats. The injection of PRP at two concentrations reduced the number and extent of the follicular atresia and inflammatory responses (p < 0.05). The expression of both ANGPT2 and KDR transcripts were significantly increased in POI rats due to enhanced inflammation, while these values were modulated after PRP administration (p < 0.05) compared to POI rats. FSH showed a decreased trend in concentration eight weeks after PRP treatment, but not statistically significant (p > 0.05). Nevertheless, a clear improvement in litter counts was found in POI rats receiving PRP compared to the non-treated POI group, being able to consider PRP as a facile, quick, accessible, safe and relatively cheap alternative therapeutic strategy to revert POI-related pathologies.

Bone Marrow Mesenchymal Stromal Cells (BMMSCs) Augment Osteointegration of Dental Implants in Type 1 Diabetic Rabbits: An X-Ray Micro-Computed Tomographic Evaluation

Background and objectives: The study aimed to investigate the effect of bone marrow mesenchymal stromal cells (BMMSCs) on implant-bone osseointegration in type I diabetic New Zealand rabbits. Materials and methods: BMMSCs harvested from healthy rabbits were processed and validated for purity and osteocyte differentiability. Mandibular incisors of diabetic and control rabbits were carefully extracted, and the sockets were plugged with collagen sponges. Platelet-rich plasma (PRP) containing osteoinductive BMMSCs, and plain PRP were injected into the collagen sponge of the right and left sockets respectively. Dental implants of 2.6 mm diameter and 10 mm length were inserted into the collagen sponge of both sockets. All the animals were sacrificed six weeks post surgery to evaluate an early stage of osseointegration; the mandibles scanned by X-ray microcomputed tomography (μCT) and subjected to 3D analysis. The μCT parameters of the right implant were paired against that of the left side of each animal and analyzed by paired T-test. Results: The preclinical evaluation of the viability and osteocyte differentiation of the BMMSCs were consistent between both the donor samples. The osseointegration of dental implants with stem cell therapy (BMMSCs + PRP + collagen) in normal and diabetic rabbits was significantly higher than that of implants with adjunctive PRP + collagen only (p < 0.05). Conclusion: Stem Cell therapy with osteoinductive BMMSCs and PRP can offer a novel approach to enhance the osseointegration of dental implants in uncontrolled diabetic patients.