The Effects of the Combination of Rhein and Platelet-Rich Plasma on Human Articular Chondrocytes.

BACKGROUND: The presence of side effects and low bioavailability of rhein has limited its use in the treatment of osteoarthritis. We aimed to evaluate the in vitro response of human articular chondrocytes to the presence of the combination of platelet-rich plasma (PRP) and rhein. METHODS: Solutions of rhein were prepared to assess solubility and select a working concentration. A stimulus with interleukin-1ß (IL-ß, 10 ng/mL) was induced for 24 h on human chondrocytes. Five treatment groups were established: control, IL-ß control, PRP, rhein, and PRP + rhein. Cell viability, cell migration, nitric oxide (NO) production, tumor necrosis factor-α (TNF-α), and gene expression analyses were carried out. RESULTS: A concentration of 50 mg/L was selected after a dose-response curve assay. Both NO and tumor TNF-α production significantly decreased after PRP and PRP + rhein treatments at 24 and 48 h. The wound healing assay revealed a significant stimulation of migration after 72 h with the PRP and PRP + rhein treatments. Expression of IL-1ß, IL-6, MMP-13, and ADAMTS-5 was significantly downregulated, particularly after treatment with the combination of PRP + rhein. CONCLUSIONS: Much of the determinations denoted a better performance of the combination of PRP and rhein in decreasing the levels of the different targets evaluated; however, this was not great enough to detect a significant difference in comparison with the PRP treatment alone.

Association of the Interleukin 1B-31*C Proinflammatory Allele with the Severity of COVID-19 Patients: A Preliminary Report.

Individuals with no known comorbidities or risk factors may develop severe coronavirus disease 2019 (COVID-19). The present study assessed the effect of certain host polymorphisms and viral lineage on the severity of COVID-19 among hospitalized patients with no known comorbidities in Mexico. The analysis included 117 unrelated hospitalized patients with COVID-19. Patients were stratified by whether they required intensive care unit (ICU) admission: the ICU group (n = 40) and non-ICU group (n = 77). COVID-19 was diagnosed on the basis of a positive severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) reverse transcription-polymerase chain reaction (RT-PCR) assay and clinical and radiographic criteria. The presence of the IL1B-31 (T/C) polymorphism was determined for all patients using PCR and nucleotide sequencing. Genotyping of the IL-4 (-590, T/C) and IL-8 (-251, T/A) polymorphisms was performed by the amplification refractory mutation system-PCR method. Genotyping of IL1-RN was performed using PCR. Viral genome sequencing was performed using the ARTIC Network amplicon sequencing protocol using a MinION. Logistic regression analysis identified the carriage of IL-1 B*-31 *C as an independent potential risk factor (odds ratio [OR] = 3.1736, 95% confidence interval [CI] = 1.0748-9.3705, p = 0.0366) for ICU admission and the presence of IL-RN*2 as a protective factor (OR = 0.4371, 95% CI = 0.1935-0.9871, p = 0.0465) against ICU admission. Under the codominant model, the CC genotype of IL1B-31 significantly increased the risk of ICU admission (OR: 6.38, 95% CI: 11.57-25.86, p < 0.024). The IL1B-31 *C-IL-4-590 *T haplotype increased the risk of ICU admission (OR = 2.53, 95% CI = 1.02-6.25, p = 0.047). The 42 SARS-CoV-2 genomes sequenced belonged to four clades, 20A-20D. No association was detected between SARS-CoV-2 clades and ICU admission or death. Thus, in patients with no known comorbidities or risk factors, the IL1B-31*C proinflammatory allele was observed to be associated with the risk of ICU admission owing to COVID-19.

Unraveling the Molecular Mechanisms Involved in HCV-Induced Carcinogenesis.

Cancer induced by a viral infection is among the leading causes of cancer. Hepatitis C Virus (HCV) is a hepatotropic oncogenic positive-sense RNA virus that leads to chronic infection, exposing the liver to a continuous process of damage and regeneration and promoting hepatocarcinogenesis. The virus promotes the development of carcinogenesis through indirect and direct molecular mechanisms such as chronic inflammation, oxidative stress, steatosis, genetic alterations, epithelial-mesenchymal transition, proliferation, and apoptosis, among others. Recently, direct-acting antivirals (DAAs) showed sustained virologic response in 95% of cases. Nevertheless, patients treated with DAAs have reported an unexpected increase in the early incidence of Hepatocellular carcinoma (HCC). Studies suggest that HCV induces epigenetic regulation through non-coding RNAs, DNA methylation, and chromatin remodeling, which modify gene expressions and induce genomic instability related to HCC development that persists with the infection's clearance. The need for a better understanding of the molecular mechanisms associated with the development of carcinogenesis is evident. The aim of this review was to unravel the molecular pathways involved in the development of carcinogenesis before, during, and after the viral infection's resolution, and how these pathways were regulated by the virus, to find control points that can be used as potential therapeutic targets.

Tiny Regulators in Viral Infection: Carving SARS-CoV-2 by miRNAs.

Viruses are microscopic biological entities that can cause diseases. Viruses require a host cell to replicate and generate progeny. Once inside, viruses hijack the main cellular machinery for their benefit, disrupting cell functions and causing detrimental effects on cell physiology. MicroRNAs are short, non-coding RNAs that regulate gene expression. Recent works have shown that cell-miRNAs can modulate antiviral defense during viral infection, and viruses can disrupt these existing miRNA networks. Furthermore, multiple RNA viruses encode their own miRNAs to evade the host immune response. In this review, we analyze the activities of both, miRNAs as pro-viral modulators and miRNAs as anti-viral agents and their relationship with the development of the disease.

Seroprevalence of Anti-SARS-CoV-2 Antibodies in Blood Donors from Nuevo Leon State, Mexico, during 2020: A Retrospective Cross-Sectional Evaluation.

The progression and distribution of the SARS-CoV-2 pandemic are continuously changing over time and can be traced by blood donors' serological survey. Here, we investigated the seroprevalence of anti-SARS-CoV-2 antibodies in blood donors in Nuevo Leon, Mexico during 2020 as a strategy for the rapid evaluation of the spread of SARS-CoV-2 and asymptomatic case detection. We collected residual plasma samples from blood donors who attended two regional donation centers from January to December of 2020 to identify changes in anti-SARS-CoV-2 IgG prevalence. Plasma samples were analyzed on the Abbott Architect instrument using the commercial Abbott SARS-CoV-2 IgG chemiluminescent assay. We found a total of 99 reactive samples from 2068 analyzed plasma samples, resulting in a raw prevalence of 4.87%. Donors aged 18-49 years were more likely to be seropositive compared to those aged >50 years (p < 0.001). Weekly seroprevalence increased from 1.8% during the early pandemic stage to 27.59% by the end of the year. Prevalence was 1.46-fold higher in females compared to males. Case geographical mapping showed that Monterrey city recorded the majority of SARS-CoV-2 cases. These results show that there is a growing trend of seroprevalence over time associated with asymptomatic infection that is unnoticed under the current epidemiological surveillance protocols.

Turnera diffusa extract attenuates profibrotic, extracellular matrix and mitochondrial markers in activated human hepatic stellate cells (HSC).

INTRODUCTION AND OBJECTIVES: Hepatic fibrosis is characterized by the accumulation of extracellular matrix which includes the accumulation of α-smooth muscle actin (α-SMA), collagen type I (COL1α1), as well as remodeling induced by metalloproteinases and tissue inhibitor of metalloproteinase (TIMPs), where hepatic stellate cells (HSCs) play a central role. In addition, the transcription factor SNAI1 (which participates in epithelial-mesenchymal transition, EMT) and mitofusin 2 (MFN2, a mitochondrial marker) plays an important role in chronic liver disease. Turnera diffusa (TD), a Mexican endemic plant, has been shown to possess antioxidant and hepatoprotective activity in vitro. We treated human HSC (LX2 cells) with a methanolic extract of Turnera diffusa (METD) to evaluate the mechanism involved in its hepatoprotective effect measured as fibrosis modulation, EMT, and mitochondrial markers. MATERIALS AND METHODS: HSC LX-2 cells were treated with METD (100 and 200ng/mL) alone or combined with TGF-ß (10ng/mL) at different time points (24, 48, and 72h). α-SMA, COL1α1, MMP2, TIMP1, SNAI1, and MFN2 mRNAs and protein levels were determined by real-time quantitative PCR and Western Blot analysis. RESULTS: We found that METD decreases COL1α1-mRNA, α-SMA, and TIMP1 protein expression in LX2 cells treated with and TGF-ß. This treatment also decreases MFN2 and TIMP1 protein expression and induces overexpression of MMP2-mRNA. CONCLUSIONS: Our results suggest that a methanolic extract of Turnera diffusa is associated with an antifibrotic effect by decreasing profibrotic and mitochondrial markers together with the possible induction of apoptosis through SNAI1 expression in activated HSC cells.

Anti­inflammatory and anti­catabolic effect of non­animal stabilized hyaluronic acid and mesenchymal stem cell­conditioned medium in an osteoarthritis coculture model.

Previous clinical studies have reported the clinical effectiveness of non­animal stabilized hyaluronic acid (NASHA) and adipose­derived mesenchymal stromal/stem cells (MSC) in the treatment of knee osteoarthritis (OA). Unlike MSC secreted mediators, in vitro anti­inflammatory effects of NASHA have not been evaluated. We aimed to evaluate and compare the anti­inflammatory effect of NASHA and MSC conditioned medium (stem cell­conditioned medium; SC­CM), in an explant­based coculture model of OA. Cartilage and synovial membrane from seven patients undergoing total knee arthroplasty were used to create a coculture system. Recombinant IL­1ß was added to the cocultures to induce inflammation. Four experimental groups were generated: i) Basal; ii) IL­1ß; iii) NASHA (NASHA + IL­1ß); and iv) SC­CM (SC­CM + IL­1ß). Glycosaminoglycans (GAG) released in the culture medium and of nitric oxide (NO) production were quantified. Gene expression in cartilage and synovium of IL­1ß, matrix metallopeptidase 13 (MMP13), ADAM metallopeptidase with thrombospondin type 1 motif 5 (ADAMTS5) and tissue inhibitor of metalloproteinases 1 (TIMP1) was measured by reverse transcription­quantitative PCR. Media GAG concentration was decreased in cocultures with NASHA and SC­CM (48 h, P<0.05; 72 h, P<0.01) compared with IL­1ß. Production of NO was significantly lower only in SC­CM after 72 h (P<0.01). In cartilage, SC­CM inhibited the expression of IL­1ß, MMP13 and ADAMTS5, while NASHA had this effect only in MMP13 and ADAMTS5. In synovium, SC­CM decreased the expression level of MMP13 and ADAMTS5, while NASHA only decreased ADAMTS5 expression. Both NASHA and SC­CM increased TIMP1 expression in cartilage and synovium. Treatments with NASHA and SC­CM were shown to be a therapeutic option that may help counteract the catabolism produced by the inflammatory state in knee OA. The anti­inflammatory mediators produced by MSC promote a lower expression of inflammatory targets in our study model.

S-adenosyl-L-methionine modifies antioxidant-enzymes, glutathione-biosynthesis and methionine adenosyltransferases-1/2 in hepatitis C virus-expressing cells.

AIM: To elucidate the mechanism(s) by which S-adenosyl-L-methionine (SAM) decreases hepatitis C virus (HCV) expression. METHODS: We examined the effects of SAM on viral expression using an HCV subgenomic replicon cell culture system. Huh7 HCV-replicon cells were treated with 1 mmol/L SAM for different times (24-72 h), then total RNA and proteins were isolated. cDNA was synthesized and real time-PCR was achieved to quantify HCV-RNA, superoxide dismutase 1 and 2 (SOD-1, SOD-2) catalase, thioredoxin 1, methionine adenosyltransferase 1A and 2A (MAT1A, MAT2A) expression, and GAPDH and RPS18 as endogenous genes. Expression of cellular and viral protein was evaluated by western-blot analysis using antibodies vs HCV-NS5A, SOD-1, SOD-2, catalase, thioredoxin-1, MAT1A, MAT2A, GAPDH and actin. Total glutathione levels were measured at different times by Ellman's recycling method (0-24 h). Reactive oxidative species (ROS) levels were quantified by the dichlorofluorescein assay (0-48 h); Pyrrolidin dithiocarbamate (PDTC) was tested as an antioxidant control and H2O2 as a positive oxidant agent. RESULTS: SAM exposition decreased HCV-RNA levels 50%-70% compared to non-treated controls (24-72 h). SAM induced a synergic antiviral effect with standard IFN treatment but it was independent of IFN signaling. In addition, 1 mmol/L SAM exposition did not modify viral RNA stability, but it needs cellular translation machinery in order to decrease HCV expression. Total glutathione levels increased upon SAM treatment in HCV-replicon cells. Transcriptional antioxidant enzyme expression (SOD-1, SOD-2 and thioredoxin-1) was increased at different times but interestingly, there was no significant change in ROS levels upon SAM treatment, contrary to what was detected with PDTC treatment, where an average 40% reduction was observed in exposed cells. There was a turnover from MAT1A/MAT2A, since MAT1A expression was increased (2.5 fold-times at 48 h) and MAT2A was diminished (from 24 h) upon SAM treatment at both the transcriptional and translational level. CONCLUSION: A likely mechanism(s) by which SAM diminish HCV expression could involve modulating antioxidant enzymes, restoring biosynthesis of glutathione and switching MAT1/MAT2 turnover in HCV expressing cells.