Prevention and treatment of rheumatoid arthritis through traditional Chinese medicine: role of the gut microbiota.

Recently, despite the increasing availability of treatments for Rheumatoid arthritis (RA), the incidence of RA and associated disability-adjusted life years have been on the rise globally in the late decades. At present, accumulating evidence has been advanced that RA is related to the gut microbiota, therefore, the therapeutic approaches for RA by regulating the gut microbiota are anticipated to become a new means of treatment. Traditional Chinese medicine (TCM) can regulate immunity, reduce inflammation and improve quality of life in various ways. Moreover, it can treat diseases by affecting the gut microbiota, which is a good way to treat RA. In this review, we mainly explore the relationship between TCM and gut microbiota regarding the perspective of treating RA. Moreover, we comprehensively summarize the roles of gut microbiota in the onset, development, progression, and prognosis of RA. Additionally, we elucidate the mechanism of TCM prevention and treatment of RA by the role of microbiota. Finally, we provide an evidence-based rationale for further investigation of microbiota-targeted intervention by TCM.

Transcription Factor JunB Suppresses Hepatitis C Virus Replication.

We previously reported that hepatitis C virus (HCV) infection activates the reactive oxygen species (ROS)/c-Jun N-terminal kinase (JNK) signaling pathway. Activation of JNK contributes to the development of liver diseases, including metabolic disorders, steatosis, liver cirrhosis and hepatocellular carcinoma. JNK is known to have numerous target genes, including JunB, a member of activator protein-1 transcription factor family. However, the roles of JunB in the HCV life cycle and HCV-associated pathogenesis remain unclear. To clarify a physiological role of JunB in HCV infection, we investigated the phosphorylation of JunB in HCV J6/JFH1-infected Huh-7.5 cells. Immunoblot analysis revealed that HCV-induced ROS/JNK activation promoted phosphorylation of JunB. The small interfering RNA (siRNA) knockdown of JunB significantly increased the amount of intracellular HCV RNA as well as the intracellular and extracellular HCV infectivity titers. Conversely, overexpression of JunB significantly reduced the amount of intracellular HCV RNA and the intracellular and extracellular HCV infectivity titers. These results suggest that JunB plays a role in inhibiting HCV propagation. Additionally, HCV-mediated JunB activation promoted hepcidin promoter activity and hepcidin mRNA levels, a key factor in modulating iron homeostasis, suggesting that JunB is involved in HCV-induced transcriptional upregulation of hepcidin. Taken together, we propose that the HCV-induced ROS/JNK/JunB signaling pathway plays roles in inhibiting HCV replication and contributing to HCV-mediated iron metabolism disorder.

CpxA/R-Controlled Nitroreductase Expression as Target for Combinatorial Therapy against Uropathogens by Promoting Reactive Oxygen Species Generation.

The antibiotic resistances emerged in uropathogens lead to accumulative treatment failure and recurrent episodes of urinary tract infection (UTI), necessitating more innovative therapeutics to curb UTI before systematic infection. In the current study, the combination of amikacin and nitrofurantoin is found to synergistically eradicate Gram-negative uropathogens in vitro and in vivo. The mechanistic analysis demonstrates that the amikacin, as an aminoglycoside, induced bacterial envelope stress by introducing mistranslated proteins, thereby constitutively activating the cpxA/R two-component system (Cpx signaling). The activation of Cpx signaling stimulates the expression of bacterial major nitroreductases (nfsA/nfsB) through soxS/marA regulons. As a result, the CpxA/R-dependent nitroreductases overexpression generates considerable quantity of lethal reactive intermediates via nitroreduction and promotes the prodrug activation of nitrofurantoin. As such, these actions together disrupt the bacterial cellular redox balance with excessively-produced reactive oxygen species (ROS) as "Domino effect", accelerating the clearance of uropathogens. Although aminoglycosides are used as proof-of-principle to elucidate the mechanism, the synergy between nitrofurantoin is generally applicable to other Cpx stimuli. To summarize, this study highlights the potential of aminoglycoside-nitrofurantoin combination to replenish the arsenal against recurrent Gram-negative uropathogens and shed light on the Cpx signaling-controlled nitroreductase as a potential target to manipulate the antibiotic susceptibility.

Natural flavonoids disrupt bacterial iron homeostasis to potentiate colistin efficacy.

In the face of the alarming rise in global antimicrobial resistance, only a handful of novel antibiotics have been developed in recent decades, necessitating innovations in therapeutic strategies to fill the void of antibiotic discovery. Here, we established a screening platform mimicking the host milieu to select antibiotic adjuvants and found three catechol-type flavonoids-7,8-dihydroxyflavone, myricetin, and luteolin-prominently potentiating the efficacy of colistin. Further mechanistic analysis demonstrated that these flavonoids are able to disrupt bacterial iron homeostasis through converting ferric iron to ferrous form. The excessive intracellular ferrous iron modulated the membrane charge of bacteria via interfering the two-component system pmrA/pmrB, thereby promoting the colistin binding and subsequent membrane damage. The potentiation of these flavonoids was further confirmed in an in vivo infection model. Collectively, the current study provided three flavonoids as colistin adjuvant to replenish our arsenals for combating bacterial infections and shed the light on the bacterial iron signaling as a promising target for antibacterial therapies.

A multicomponent gas wavelength selection method based on an absorbance mathematical model.

In order to quickly and accurately determine the optimal absorption spectra of the gases to be measured, a method for selecting the optimal wavelengths for multicomponent gases was proposed. A mathematical model of the absorbance of multicomponent gases was established, and the selection conditions of the optimal wavelengths were analyzed from the perspective of geometric significance. The best measurement spectra for the gas mixture of CO2, CH4, and C2H2 were determined and the gas mixture was measured using the supercontinuum laser absorption spectroscopy (SCLAS) technique, and the partial least squares (PLS) model and the least squares (LS) model were established to quantify the experimental results. The results showed that the PLS model had better prediction performance. The root mean square error (RMSE) of the calibration set PLS model for CO2 and CH4 was 0.1652 and 0.0053, the RMSE of the prediction set PLS model was 0.1991 and 0.0163, and the determination coefficient (R2) of the models was above 0.9. The experimental results show that the optimal wavelength selection method for multicomponent gases proposed in this study can effectively determine the optimal measurement spectral lines for the gases to be measured.

Hepatitis C Virus-Induced ROS/JNK Signaling Pathway Activates the E3 Ubiquitin Ligase Itch to Promote the Release of HCV Particles via Polyubiquitylation of VPS4A.

We previously reported that hepatitis C virus (HCV) infection activates the reactive oxygen species (ROS)/c-Jun N-terminal kinase (JNK) signaling pathway. However, the roles of ROS/JNK activation in the HCV life cycle remain unclear. We sought to identify a novel role of the ROS/JNK signaling pathway in the HCV life cycle. Immunoblot analysis revealed that HCV-induced ROS/JNK activation promoted phosphorylation of Itch, a HECT-type E3 ubiquitin ligase, leading to activation of Itch. The small interfering RNA (siRNA) knockdown of Itch significantly reduced the extracellular HCV infectivity titers, HCV RNA, and HCV core protein without affecting intracellular HCV infectivity titers, HCV RNA, and HCV proteins, suggesting that Itch is involved in the release of HCV particles. HCV-mediated JNK/Itch activation specifically promoted polyubiquitylation of an AAA-type ATPase, VPS4A, but not VPS4B, required to form multivesicular bodies. Site-directed mutagenesis revealed that two lysine residues (K23 and K121) on VPS4A were important for VPS4A polyubiquitylation. The siRNA knockdown of VPS4A, but not VPS4B, significantly reduced extracellular HCV infectivity titers. Coimmunoprecipitation analysis revealed that HCV infection specifically enhanced the interaction between CHMP1B, a subunit of endosomal sorting complexes required for transport (ESCRT)-III complex, and VPS4A, but not VPS4B, whereas VPS4A K23R/K121R greatly reduced the interaction with CHMP1B. HCV infection significantly increased ATPase activity of VPS4A, but not VPS4A K23R/K121R or VPS4B, suggesting that HCV-mediated polyubiquitylation of VPS4A contributes to activation of VPS4A. Taken together, we propose that the HCV-induced ROS/JNK/Itch signaling pathway promotes VPS4A polyubiquitylation, leading to enhanced VPS4A-CHMP1B interaction and promotion of VPS4A ATPase activity, thereby promoting the release of HCV particles. IMPORTANCE The ROS/JNK signaling pathway contributes to liver diseases, including steatosis, metabolic disorders, and hepatocellular carcinoma. We previously reported that HCV activates the ROS/JNK signaling pathway, leading to the enhancement of hepatic gluconeogenesis and apoptosis induction. This study further demonstrates that the HCV-induced ROS/JNK signaling pathway activates the E3 ubiquitin ligase Itch to promote release of HCV particles via polyubiquitylation of VPS4A. We provide evidence suggesting that HCV infection promotes the ROS/JNK/Itch signaling pathway and ESCRT/VPS4A machinery to release infectious HCV particles. Our results may lead to a better understanding of the mechanistic details of HCV particle release.

Prevalence and Distribution of Rotavirus Genotypes Among Children With Acute Gastroenteritis in Areas Other Than Java Island, Indonesia, 2016-2018.

Group A rotaviruses (RVAs) are the leading cause of acute gastroenteritis, which is often associated with severe symptoms in children under 5 years old. Genetic reassortments and interspecies transmission commonly occur, resulting in a great diversity of RVA circulating in the world. The aim of this study is to determine the prevalence and distribution of RVA genotypes among children in Indonesia over the years 2016-2018 across representative areas of the country. Stool samples were collected from 202 pediatric patients with acute gastroenteritis in three regions of Indonesia (West Nusa Tenggara, South Sumatra, and West Papua) in 2016-2018. Rotavirus G and P genotypes were determined by reverse transcription PCR (RT-PCR) and direct sequencing analysis. The prevalences of RVA in South Sumatra (55.4%) and West Papua (54.0%) were significantly higher than that in East Java (31.7%) as determined in our previous study. The prevalence in West Nusa Tenggara (42.6%) was the lowest among three regions, but higher than that in East Java. Interestingly, equine-like G3 rotavirus strains were found as predominant strains in South Sumatra in 2016 and in West Papua in 2017-2018. Moreover, the equine-like G3 strains in South Sumatra detected in 2016 were completely replaced by human G1 and G2 in 2018. In conclusion, RVA infection in South Sumatra and West Papua was highly endemic. Equine-like G3 strains were also spread to South Sumatra (West Indonesia) and West Papua (East Indonesia), as well as Java Island. Dynamic change in rotavirus genotypes from equine-like G3 to human genotypes was also observed. Continuous monitoring may be warranted in isolated areas in Indonesia.

Association Between HBx Variations and Development of Severe Liver Disease Among Indonesian Patients.

Multi-site mutations in the hepatitis B virus (HBV) X gene are often found in patients with advanced liver diseases such as liver cirrhosis and hepatocellular carcinoma. It has been reported that modifications in the X protein play crucial roles in the development of HBV-related severe liver disease. However, the prevalence of genetic variations in Indonesian strains has not been systematically assessed. In this study, we sought to investigate the profile of nonsynonymous mutations in the X gene. Overall, 114 Indonesian HBV strains, including 12 in-house samples, were retrieved from GenBank. The mutation frequency in the X gene was compared among strains obtained from patients with chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma. The mutation frequencies of the domain and basal core promoter regions were significantly greater in advanced liver diseases compared with chronic hepatitis. In addition, the double mutation K130M/V131I and the triple mutation N88V/K130M/V131I were associated with a 2.5 times higher risk of advanced liver disease. However, the roles of two novel X gene mutations (A12S/T and L16F/P) on hepatocarcinogenesis are unclear relative to wild-type X gene. In conclusion, the development of multi-site mutations in the X gene may represent a strategy by which HBV can escape immune surveillance and thus contribute to hepatocarcinogenesis, even though the biological roles of some variants remain unclear.

Association between quasispecies variants of hepatitis B virus, as detected by high­throughput sequencing, and progression of advanced liver disease in Indonesian patients.

Mutations in the hepatitis B virus (HBV) X region and truncation of the preS2 region are well­known to affect the progression of liver disease. Recently, it has been observed that an increasing number of S region quasispecies variants are associated with disease progression. However, few studies have analysed quasispecies of the whole genome using high­throughput sequencing methods. Using high­throughput sequencing, whole­genome variations in 12 Indonesian patients infected with HBV (eight with advanced liver disease and four with chronic hepatitis) were examined. Variations with cut­off values of ≥1% of the total viral population were investigated. It was revealed that within the four open reading frames, quasispecies variations of the S and X regions were higher in advanced liver diseases compared with in chronic hepatitis (S region: 89.53 vs. 50.69%, P=0.047; X region: 76.95 vs. 35.88%, P=0.044). Notably, the mutation frequencies in the basal core promoter, B cell epitope, RT Box G, RNAseH and small S region were greater in advanced liver disease. The proportion of quasispecies variants increased for the majority of the mutations, with the exception for W196* in the small S gene, during disease progression. The present study demonstrated that quasispecies in the S and X regions of the HBV genome changed during disease progression and were associated with advanced liver disease development in Indonesian patients with HBV.

Early changes in quasispecies variant after antiviral therapy for chronic hepatitis B.

Hepatitis B virus (HBV) polymerase gene is targeted by nucleos(t)ide analogues (NUC), but it is unclear how HBV quasispecies of whole genome changes during early period of NUC treatment. To understand the unknown region of drug sensitivity and treatment resistance, HBV quasispecies of whole genome during early period of NUC treatment was examined using ultra­deep sequencing. Eleven patients with chronic HBV infection who received NUC treatment were enrolled in the current study. Viral DNA was extracted from serum samples before and early period of NUC treatment. Polymerase chain reaction analysis was subsequently performed on the DNA products. The viral quasispecies of the entire genome was analyzed by ultra­deep sequencing. The regions and positions corresponding to the changes in the quasispecies were investigated before and early period of NUC treatment. The secondary structure changes were predicted by mutations/substitutions detected using Lasergene Protean v14.1 software. The frequency of quasispecies variants increased significantly in the polymerase domain from before to early period of NUC treatment (3.08±1.28 vs. 3.51±1.47%, P<0.008), particularly the reverse transcription (RT) domain (3.76±1.25 vs. 4.52±1.37%, P<0.012). In addition, increased variation detected from HBsAg domain showed statistically significant during NUC treatment (6.81±3.26 vs. 7.81±3.26%, P<0.040). The amino acid (aa) mutations/substitutions were detected and compared from before to early period of treatment. Interestingly, most of them were located in the RT region (RT1 motif: aa21­aa51) and small S region in the early duration of NUC treatment. Furthermore, several mutation patterns, such as cI97L and cP130T showed alterations in the secondary structure and predicted antigenicity of HBV protein. Although the HBV whole genome can be affected by NUC treatment, RT 1 motif region and small S region are more sensitive to the early period of NUC treatment. This study suggested the initial changes of HBV quasispecies might affect the long­term drug sensitivity and resistance to NUC treatment.

Genetic polymorphisms of HLA-DP and isolated anti-HBc are important subsets of occult hepatitis B infection in Indonesian blood donors: a case-control study.

BACKGROUND: Occult hepatitis B infection (OBI) is defined as the presence of hepatitis B virus (HBV) DNA in the serum and/or liver in HBsAg-negative individuals. OBI is associated with the risk of viral transmission, especially in developing countries, and with progressive liver disease and reactivation in immunosuppressive patients. The objective of this study was to evaluate the relation of OBI to HLA-DP single nucleotide polymorphisms (SNPs) encoding antigen-binding sites for the immune response to HBV infection. As HLA-DP variants affect the mRNA expression of HLA-DPA1 and HLA-DPB1 in the liver, we hypothesised that high levels of HLA-DPA1 and HLA-DPB1 expression favour OBI development. METHODS: The study enrolled 456 Indonesian healthy blood donors (HBsAg negative). OBI was defined as the presence of HBV-DNA in at least two of four open reading frames (ORFs) of the HBV genome detected by nested PCR. SNPs in HLA-DPA1 (rs3077) and HLA-DPB1 (rs3135021, rs9277535, and rs2281388) were genotyped using real-time Taqman® genotyping assays. RESULTS: Of 122 samples positive for anti-HBs and/or anti-HBc, 17 were determined as OBI. The minor allele in rs3077 was significantly correlated with OBI [odds ratio (OR) = 3.87, 95% confidence interval (CI) = 1.58-9.49, p = 0.0015]. The prevalence of the minor allele (T) was significantly higher in subjects with OBI than in those without (59% and 33%, respectively). The combination of haplotype markers (TGA for rs3077-rs3135021-rs9277535) was associated with increased risk of OBI (OR = 4.90, 95%CI = 1.12-21.52 p = 0.038). The prevalence of OBI was highest in the isolated anti-HBc group among the three seropositive categories: anti-HBs <500 mIU/ml, anti-HBs ≥500 mIU/ml, and isolated anti-HBc (29.41%, p = 0.014). CONCLUSION: Genetic variants of HLA-DP and the presence of anti-HBc are important predictors of OBI in Indonesian blood donors. TRIAL REGISTRATION: Ref: KE/FK/194/EC; registered 01 March 2013. Continuing approval Ref: KE/FK/536/EC; registered 12 May 2014.

Protective effects of HLA-DPA1/DPB1 variants against Hepatitis B virus infection in an Indonesian population.

Human leukocyte antigen (HLA) DPA1/DPB1 variants have been reported to influence Hepatitis B virus (HBV) infection. HLA-DPA1/DPB1 plays a pivotal role in antigen presentation to CD4(+) helper T cells and influences the outcome of HBV infection. To investigate the influence of HLA-DP variants on the outcome of HBV infection in an Indonesian population where it has the third-highest prevalence of HBV infection worldwide, we performed a case-control study of 686 participants, including patients with HBV-related advanced or nonadvanced liver disease, patients with spontaneously resolved HBV, and healthy controls. Single-nucleotide polymorphisms in HLA-DPA1 (rs3077) and HLA-DPB1 (rs3135021, rs9277535, and rs228388) were genotyped using real-time TaqMan® genotyping assays. Because rs2281388 deviated from Hardy-Weinberg equilibrium, it was excluded from subsequent analyses. The results of logistic regression analyses showed that the HLA-DPB1 rs9277535 variants were associated with a reduced risk of persistent HBV infection (odds ratio [OR] 0.70, 95% confidence interval [95% CI] 0.52-0.96, P=0.026, additive genetic model; OR 0.60, 95% CI 0.38-0.96, P=0.033, dominant genetic model). The HLA-DPA1 rs3077 variant was associated with a protective effect increasing the spontaneously resolved HBV infection (OR 0.64, 95% CI 0.41-0.98, P=0.039, dominant genetic model). By contrast, the HLA-DPB1 rs3135021 variant was not associated with the outcome of HBV infection, including susceptibility, spontaneously resolved, or disease progression. Combinations of haplotype markers were also associated with HBV susceptibility (CA for rs3077-rs9277535, OR 0.57, 95% CI 0.36-0.92, P=0.021; GA for rs3135021-rs9277535, OR 0.56, 95% CI 0.36-0.86, P=0.0087). In conclusion, these findings confirm that HLA-DPA1/DPB1 variants were associated with the outcomes of HBV infection in an Indonesian population.

Ultradeep Sequencing for Detection of Quasispecies Variants in the Major Hydrophilic Region of Hepatitis B Virus in Indonesian Patients.

Quasispecies of hepatitis B virus (HBV) with variations in the major hydrophilic region (MHR) of the HBV surface antigen (HBsAg) can evolve during infection, allowing HBV to evade neutralizing antibodies. These escape variants may contribute to chronic infections. In this study, we looked for MHR variants in HBV quasispecies using ultradeep sequencing and evaluated the relationship between these variants and clinical manifestations in infected patients. We enrolled 30 Indonesian patients with hepatitis B infection (11 with chronic hepatitis and 19 with advanced liver disease). The most common subgenotype/subtype of HBV was B3/adw (97%). The HBsAg titer was lower in patients with advanced liver disease than that in patients with chronic hepatitis. The MHR variants were grouped based on the percentage of the viral population affected: major, ≥20% of the total population; intermediate, 5% to <20%; and minor, 1% to <5%. The rates of MHR variation that were present in the major and intermediate viral population were significantly greater in patients with advanced liver disease than those in chronic patients. The most frequent MHR variants related to immune evasion in the major and intermediate populations were P120Q/T, T123A, P127T, Q129H/R, M133L/T, and G145R. The major population of MHR variants causing impaired of HBsAg secretion (e.g., G119R, Q129R, T140I, and G145R) was detected only in advanced liver disease patients. This is the first study to use ultradeep sequencing for the detection of MHR variants of HBV quasispecies in Indonesian patients. We found that a greater number of MHR variations was related to disease severity and reduced likelihood of HBsAg titer.