Investigation of the Development of Hypersensitivity and Hyperalgesia After Repeated Application of Platelet-Rich Plasma in Rats: An Experimental Study

Repeated platelet-rich plasma injections improve erectile dysfunction in a rat model of hyperhomocysteinemia

ABSTRACT

Platelet-rich plasma (PRP) shows promise as a regenerative modality for mild-to-moderate erectile dysfunction (ED). However, its efficacy in treating severe ED remains unknown. Blood samples from 8-week-old male rats were used to prepare PRP through a two-step centrifugation procedure, followed by chitosan activation and freeze thaw cycle. A hyperhomocysteinemia (HHcy)-related ED model was established using a methionine-enriched diet, and an apomorphine (APO) test was conducted during the 4 th week. APO-negative rats were divided into two groups and were injected with PRP or saline every 2 weeks. Erectile function and histological analyses of the corpus cavernosum were performed during the 16 th week. The results revealed that erectile function was significantly impaired in rats with HHcy-related ED compared to that in age-matched rats but was improved by repeated PRP injections. Immunofluorescence staining revealed a reduction in reactive oxygen species and additional benefits on the recovery of structures within the corpus cavernosum in rats that received PRP treatment compared to those in the saline-injected control group. Therefore, PRP could enhance functional and structural recovery in a severe HHcy-related ED model. A notable strength of the present study lies in the use of a repeated intracavernous injection method, mirroring protocols used in human studies, which offers more reliable results for translating the findings to humans.

Platelet-Rich Plasma (PRP) in the Treatment of Long COVID Olfactory Disorders: A Comprehensive Review

Background: Long COVID has brought numerous challenges to healthcare, with olfactory dysfunction (OD) being a particularly distressing outcome for many patients. The persistent loss of smell significantly diminishes the affected individual's quality of life. Recent attention has been drawn to the potential of platelet-rich plasma (PRP) therapy as a treatment for OD. This comprehensive review aims to evaluate the effectiveness of PRP therapy in ameliorating OD, especially when associated with long-term COVID-19. Methods: We executed a comprehensive search of the literature, encompassing clinical trials and observational studies that utilized PRP in treating OD limited to COVID-19. We retrieved and comprehensively discussed data such as design, participant demographics, and reported outcomes, focusing on the efficacy and safety of PRP therapy for OD in COVID-19 patients. Results: Our comprehensive analysis interestingly found promising perspectives for PRP in OD following COVID-19 infection. The collective data indicate that PRP therapy contributed to a significant improvement in olfactory function after COVID-19 infection. Conclusions: The evidence amassed suggests that PRP is a promising and safe therapeutic option for OD, including cases attributable to Long COVID-19. The observed uniform enhancement of olfactory function in patients receiving PRP highlights the necessity for well-designed, controlled trials. Such studies would help to refine treatment protocols and more definitively ascertain the efficacy of PRP in a broader, more varied patient cohort.

Use of Activated Platelet-Rich Plasma (A-PRP) on Alopecia: A Systematic Review and Meta-Analysis

Alopecia affects perceptions of age, beauty, success, and adaptability. Hair loss can be caused by genetic, physiological, environmental, and immunologic factors. The current treatment for alopecia is varied. This systematic review and meta-analysis evaluates activated platelet rich plasma (A-PRP) for alopecia treatment. The objective of this review was to assess the clinical efficacy and safety of A-PRP injections in alopecia patients. We compared the safety, limitations, and outcomes of A-PRP use with those of previous research on alopecia. We searched PubMed, EMBASE, the Cochrane Database, and Google Scholar for relevant articles. We included all primary clinical studies involving patients that evaluated A-PRP. Twenty-nine articles, which included 864 patients, met the eligibility criteria and were analyzed for qualitative review. Our review found 27 studies that indicated A-PRP was significantly effective in treating alopecia, especially for improving hair density before and after therapy (n = 184, mean difference [MD] = 46.5, I2 = 88%, 95% CI: 29.63, 63.37, P < .00001), as well as when comparison was made between treatment and control groups (n = 88, MD = 31.61, I2 = 80%, 95% CI: 6.99, 56.22, P = .01), and of terminal hair density between treatment and control groups (n = 55, MD = 26.03, I2 = 25%, 95% CI: 8.08, 43.98, P = .004); hair counts after therapy (n = 85, MD = 12.79, I2 = 83%, 95% CI: -5.53, 31.12, P = .0006); promoting hair regrowth; folliculogenesis; reducing hair loss; combining with follicular unit extraction (FUE) surgery; and initiating the hair cycle. Two studies did not report significant results. This is the first systematic review and meta-analysis of A-PRP as a treatment option for alopecia. A-PRP appears to be a promising and safe method for treating alopecia.

LEVEL OF EVIDENCE: 4

Platelet-rich Plasma Improves Radiotherapy-induced Emotional Disorder and Cognitive Dysfunction, Neuroinflammation in Aged Rats by Inhibiting the Activation of NLRP3 Inflammasomes

Although radiotherapy (RT) is the preferred treatment for elderly patients with brain tumors, certain negative effects can't be ignored. Fortunately, platelet-rich plasma (PRP) presents with a promising potential for the treatment of neurological diseases. Therefore, this study aimed to explore the effect of PRP on neuroinflammation, emotional disorder and cognitive dysfunction induced by RT in aged rats. Firstly, whole brain RT (WBRT) model was established by whole brain irradiation with 10 Gy of 6-MeV electron beam in rats. Next, twenty 20-month-old female SD rats were divided into four groups (sham group, PRP group, WBRT group, and WBRT + PRP group) according different treatments. After that, the cognitive dysfunction and depression-like behavior of rats were examined by novel object recognition test (NORT), Morris water maze test (MWM), open field test (OFT) and elevated plus maze test (EPM). Besides, immunohistochemistry was used to detect the expression of microglial marker protein Iba-1 in rat hippocampus; enzyme linked immunosorbent assay (ELISA) to examine the levels of pro-inflammatory cytokines tumor necrosis factor-alpha (TNF-α), interleukin (IL)-1 beta (IL-1β), IL-18, and monocyte chemoattractant protein 1 (MCP-1) in rat hippocampus; real-time quantitative reverse transcription PCR (qRT-PCR) and western blot to measure the levels of neurotrophic factors brain-derived neurotrophic factor (BDNF), tropomyosin-related kinase B receptor (TrkB), and nerve growth factor (NGF) in rat hippocampus; and western blot also to observe the protein expression levels of NOD-like receptor protein 3 (NLRP3), caspase-1, apoptosis-associated speck-like protein containing a CARD (ASC), and IL-1β in rat hippocampus. After experiments, some results obtained were shown as follows. PRP could significantly improve learning and memory ability and depression-like behavior, increase the level of neurotrophic factors, inhibit the activation of microglia and decrease the level of pro-inflammatory factors in WBRT rats. In addition, PRP significantly inhibited the activation of NLRP3 inflammasomes. To sum up, PRP can ameliorate neuroinflammation, emotional disorder and cognitive dysfunction induced by RT in aged rats, and the mechanism may be related to its inhibitory effect on NLRP3 inflammasome activation.

Regenerative medicine for neuropathic pain: physiology, ultrasound and therapies with a focus on alpha-2-macroglobulin

The currently available drugs to treat neuropathic pain do not provide adequate pain management. As such, other treatments including stem cells, platelet-rich plasma and plasma-derived molecules such as alpha-2 macroglobulin (A2M) are being explored because they show promising potential for neuropathic pain. The various mechanisms and immunomodulatory effects could be a desirable approach in targeting neuropathic pain. This review indicates that A2M can be highly efficacious due to its conformational change during activation and specificity of action on various cytokines. Its ability to reduce neuropathic pain can further the future of neuropathic intervention. However, there is a lack of robust clinical studies and thus further research is needed to verify and expand the understanding of its therapeutic effects.

Systematic review: The platelet-rich plasma use in female androgenetic alopecia as effective autologous treatment of regenerative plastic surgery

BACKGROUND

The number of clinical trials evaluating platelet-rich plasma (PRP) efficacy in female androgenetic alopecia (F-AGA) has exponentially increased during the last five years. A systematic review focused on this specific field has been performed by assessing the local infiltrations of PRP compared with any control for F-AGA in the selected studies.

OBJECTIVES

The aim of this study was to evaluate the safety and efficacy of the use of PRP in F-AGA.

METHODS

The protocol was developed in accordance with the Preferred Reporting for Items for Systematic Reviews and Meta-Analyses Protocols (PRISMA-P) guidelines. A multistep search of PubMed, MEDLINE, Embase, PreMEDLINE, Ebase, CINAHL, PsycINFO, Clinicaltrials.gov, Scopus database, and Cochrane databases has been performed to identify papers on female pattern hair loss (FPHL) treatment with PRP. Of the 63 articles initially identified, 11 articles focusing on AGA were selected and, consequently, only 5 articles focused exclusively on F-AGA were analyzed. Of this amount, 3 articles were randomized-controlled trials (RCTs), 1 clinical trial, and 1 double-blind placebo-controlled pilot study (DBPCPS). The studies included had to match predetermined criteria according to the PICOS (patients, intervention, comparator, outcomes, and study design) approach.

RESULTS

Eight percent of the articles selected and analyzed, reported a positive effect of PRP for F-AGA treatment. The information analyzed highlights the positive effects of PRP on F-AGA, without major side effects and thus, it may be considered as a safe and effective alternative procedure to treat hair loss compared with traditional drugs as Minoxidil® and Finasteride®.

CONCLUSIONS

The use of PRP in F-AGA was safe and effective for F-AGA.

Does Estradiol Level in Platelet-Rich Plasma Improve Efficacy of Androgenic Alopecia Treatment?

BACKGROUND

Although some studies in the literature report that autologous and homologous platelet-rich plasma (PRP) can be employed in the treatment of androgenic alopecia (AGA), no study, to the authors' knowledge, has examined the estrogen concentration of prepared PRP.

OBJECTIVES

The authors aimed to determine the presence of estrogen in PRP and to investigate the effect of estrogen concentration of PRP on AGA treatment.

METHODS

Between 2017 and 2018, 30 male patients with hair loss complaints were included in this prospective study. Autologous PRP was injected in patients in Group 1. Homologous PRP with high estrogen levels was injected in the patients in Group 2. PRP was injected in both groups 4 times at 0, 1, 3, and 6 months. The obtained photographs were evaluated and hair densities of each patient at controls were calculated.

RESULTS

The mean estrogen level measured in PRP was statistically significantly higher in Group 2. In both groups, the increase in hair density was observed from the first month, but this increase was statistically significantly higher in all controls in Group 2. In Group 2, there was a statistically significant increase in the 1st and 3rd months compared with the previous control, but there was no difference between the 6th and 12th months and the 3rd month.

CONCLUSIONS

Increased hair density is greater and earlier in the group receiving estrogen-rich PRP than in the group utilizing autologous PRP. The authors think that estrogen-rich PRP may be employed in the treatment of AGA in the presence of an appropriate donor.

LEVEL OF EVIDENCE: 2