Fujian cytoplasmic male sterility and the fertility restorer gene OsRf19 provide a promising breeding system for hybrid rice.

Cytoplasmic male sterility (CMS) determined by mitochondrial genes and restorer of fertility (Rf) controlled by nuclear-encoded genes provide the breeding systems of many hybrid crops for the utilization of heterosis. Although several CMS/Rf systems have been widely exploited in rice, hybrid breeding using these systems has encountered difficulties due to either fertility instability or complications of two-locus inheritance or both. In this work, we characterized a type of CMS, Fujian Abortive cytoplasmic male sterility (CMS-FA), with stable sporophytic male sterility and a nuclear restorer gene that completely restores hybrid fertility. CMS is caused by the chimeric open reading frame FA182 that specifically occurs in the mitochondrial genome of CMS-FA rice. The restorer gene OsRf19 encodes a pentatricopeptide repeat (PPR) protein targeted to mitochondria, where it mediates the cleavage of FA182 transcripts, thus restoring male fertility. Comparative sequence analysis revealed that OsRf19 originated through a recent duplication in wild rice relatives, sharing a common ancestor with OsRf1a/OsRf5, a fertility restorer gene for Boro II and Hong-Lian CMS. We developed six restorer lines by introgressing OsRf19 into parental lines of elite CMS-WA hybrids; hybrids produced from these lines showed equivalent or better agronomic performance relative to their counterparts based on the CMS-WA system. These results demonstrate that CMS-FA/OsRf19 provides a highly promising system for future hybrid rice breeding.

GLW7.1, a Strong Functional Allele of Ghd7, Enhances Grain Size in Rice.

Grain size is a key determinant of both grain weight and grain quality. Here, we report the map-based cloning of a novel quantitative trait locus (QTL), GLW7.1 (Grain Length, Width and Weight 7.1), which encodes the CCT motif family protein, GHD7. The QTL is located in a 53 kb deletion fragment in the cultivar Jin23B, compared with the cultivar CR071. Scanning electron microscopy analysis and expression analysis revealed that GLW7.1 promotes the transcription of several cell division and expansion genes, further resulting in a larger cell size and increased cell number, and finally enhancing the grain size as well as grain weight. GLW7.1 could also increase endogenous GA content by up-regulating the expression of GA biosynthesis genes. Yeast two-hybrid assays and split firefly luciferase complementation assays revealed the interactions of GHD7 with seven grain-size-related proteins and the rice DELLA protein SLR1. Haplotype analysis and transcription activation assay revealed the effect of six amino acid substitutions on GHD7 activation activity. Additionally, the NIL with GLW7.1 showed reduced chalkiness and improved cooking and eating quality. These findings provide a new insight into the role of Ghd7 and confirm the great potential of the GLW7.1 allele in simultaneously improving grain yield and quality.

Leptospira interrogans induces uterine inflammatory responses and abnormal expression of extracellular matrix proteins in dogs.

Leptospira interrogans (L. interrogans), a worldwide zoonosis, infect humans and animals. In dogs, four syndromes caused by leptospirosis have been identified: icteric, hemorrhagic, uremic (Stuttgart disease) and reproductive (abortion and premature or weak pups), and also it caused inflammation. Extracellular matrix (ECM) is a complex mixture of matrix molecules that is crucial to the reproduction. Both inflammatory response and ECM are closed relative to reproductive. The aim of this study was to clarify how L. interrogans affected the uterus of dogs, by focusing on the inflammatory responses, and ECM expression in dogs uterine tissue infected by L. interrogans. In the present study, 27 dogs were divided into 3 groups, intrauterine infusion with L. interrogans, to make uterine infection, sterile EMJH, and normal saline as a control, respectively. The uteruses were removed by surgical operation in 10, 20, and 30 days, respectively. The methods of histopathological analysis, ELISA, Western blot and qPCR were used. The results showed that L. interrogans induced significantly inflammatory responses, which were characterized by inflammatory cellular infiltration and high expression levels of tumor necrosis factor α (TNF-α), interleukin-1ß (IL-1ß) and interleukin-6 (IL-6) in uterine tissue of these dogs. Furthermore, L. interrogans strongly down-regulated the expression of ECM (collagens (CL) IV, fibronectins (FN) and laminins (LN)) in mRNA and protein levels. These data indicated that strongly inflammatory responses, and abnormal regulation of ECM might contribute to the proliferation of dogs infected by L. interrogans.

Efficacy of cefepime, ertapenem and norfloxacin against leptospirosis and for the clearance of pathogens in a hamster model.

Animals and humans with severe leptospirosis may require empirical treatment. Although many antibiotics are active against multiple leptospira serovars in vitro, their efficacy in vivo is limited. We evaluated the efficacy of cefepime (daily dose: 2, 5, 10, and 20 mg/kg), ertapenem (daily dose: 2.5, 5, and 10 mg/kg) and norfloxacin (daily dose: 20, 40, and 80 mg/kg) for the treatment of leptospirosis and the ability to clear leptospira in target organs (liver, kidney, lung, heart, and spleen) in a lethal hamster model using Leptospira interrogans serovar Autumnalis. The histopathology of infected kidney, lung and liver was also evaluated using hematoxylin and eosin stain (H&E stain). All untreated animals, serving as a negative control, died with leptospira existing in the target organs between the 5th and 7th day after infection. All of the treated groups displayed improved survival compared to the untreated group and demonstrated a dose-dependent decrease in the presence of leptospira in the target organs. Cefepime showed survival benefit comparable to the standard treatment, doxycycline. We conclude that all of the antibiotics tested in vivo produce a statistically significant survival advantage, alleviate tissue injury and decrease the abundance of leptospira in target organs.

Inhibitory effects of astragalin on lipopolysaccharide-induced inflammatory response in mouse mammary epithelial cells.

BACKGROUND: Tea brewed from the leaves of persimmon or Rosa agrestis have several medical functions including treating allergy, antiatopic dermatitis, and anti-inflammatory effects. The objective of this study was to investigate the molecular mechanisms of astragalin, a main flavonoid component isolated from these herbs, in modifying lipopolysaccharide (LPS)-induced signaling pathways in primary cultured mouse mammary epithelial cells (mMECs). MATERIALS AND METHODS: The mMECs were treated with LPS in the absence or presence of different concentrations of astragalin. The expression of proinflammatory cytokines tumor necrosis factor α, and interleukin 6, as well as nitric oxide production were determined by enzyme-linked immunosorbent assay and Griess reaction, respectively. Cyclooxygenase-2, inducible nitric oxide synthase, toll-like receptor 4 (TLR4), nuclear factor-κB (NF-κB), inhibitor protein of NF-κB (IκBα), P38, extracellular signal-regulated kinase, and c-Jun N-terminal kinase were measured by Western blot. RESULTS: The results showed that astragalin suppressed the expression of tumor necrosis factor α, interleukin 6, and nitric oxide in a dose-dependent manner in mMECs. Western blot results showed that the expression of inducible nitric oxide synthase and cyclooxygenase-2 was inhibited by astragalin. Besides, astragalin efficiently decreased LPS-induced TLR4 expression, NF-κB activation, IκBα degradation, and the phosphorylation of p38, extracellular signal-regulated kinase in BMECs. CONCLUSIONS: Our results indicated that astragalin exerts anti-inflammatory properties possibly via the inactivation of TLR4-mediated NF-κB and mitogen-activated protein kinases signaling pathways in LPS-stimulated mMECs. Thus, astragalin may be a potential therapeutic agent for bovine mastitis.

[Analysis of XRD spectral characteristics of soil clay mineral in two typical cultivated soils].

The present paper took black soil and chernozem, the typical cultivated soil in major grain producing area of Northeast, as the study object, and determinated the soil particle composition characteristics of two cultivated soils under the same climate and location. Then XRD was used to study the composition and difference of clay mineral in two kinds of soil and the evolutionary mechanism was explored. The results showed that the two kinds of soil particles were composed mainly of the sand, followed by clay and silt. When the particle accumulation rate reached 50%, the central particle size was in the 15-130 microm interval. Except for black soil profile of Shengli Xiang, the content of clay showed converse sequence to the central particle in two soils. Clay accumulated under upper layer (18.82%) in black soil profile while under caliche layer (17.41%) in chernozem profile. Clay content was the least in parent material horizon except in black profile of Quanyanling. Analysis of clay XRD atlas showed that the difference lied in not only the strength of diffraction peak, but also in the mineral composition. The main contents of black soil and chernozem were both 2 : 1 clay, the composition of black soil was smectite/illite mixed layer-illite-vermiculite and that of chernozem was S/I mixture-illite-montmorillonite, and both of them contained little kaolinite, chlorite, quartz and other primary mineral. This paper used XRD to determine the characteristics of clay minerals comprehensively, and analyzed two kinds of typical cultivated soil comparatively, and it was a new perspective of soil minerals study.

[Research on characteristics of soil clay mineral evolution in paddy field and dry land by XRD spectrum].

The present paper took the typical saline-alkali soil in Jilin province as study object, and determinated the soil clay mineral composition characteristics of soil in paddy field and dry land. Then XRD spectrum was used to analyze the evolutionary mechanism of clay mineral in the two kinds of soil. The results showed that the physical and chemical properties of soil in paddy field were better than those in dry land, and paddy field would promote the weathering of mineral particles in saline-alkali soil and enhance the silt content. Paddy field soil showed a strong potassium-removal process, with a higher degree of clay mineral hydration and lower degree of illite crystallinity. Analysis of XRD spectrum showed that the clay mineral composition was similar in two kinds of soil, while the intensity and position of diffraction peak showed difference. The evolution process of clay mineral in dry land was S/I mixture-->vermiculite, while in paddy field it was S/I mixture-->vermiculite-->kaolinite. One kind of hydroxylated 'chlorite' mineral would appear in saline-alkali soil in long-term cultivated paddy field. Taking into account that the physical and chemical properties of soil in paddy field were better then those in dry land, we could know that paddy field could help much improve soil structure, cultivate high-fertility soil and improve saline-alkali soil. This paper used XRD spectrum to determine the characteristics of clay minerals comprehensively, and analyzed two'kinds of land use comparatively, and was a new perspective of soil minerals study.

Low skeletal muscle mass index and all-cause mortality risk in adults: A systematic review and meta-analysis of prospective cohort studies.

OBJECTIVE: The relationship between low skeletal muscle mass index (SMI) and all-cause mortality risk in the general adults remains unclear. Our study was conducted to examine and quantify the associations between low SMI and all-cause mortality risks. METHODS: PubMed, Web of Science, and Cochrane Library for primary data sources and references to relevant publications retrieved until 1 April 2023. A random-effect model, subgroup analyses, meta-regression, sensitivity analysis, and publication bias were conducted using STATA 16.0. RESULTS: Sixteen prospective studies were included in the meta-analysis of low SMI and the risk of all-cause mortality. A total of 11696 deaths were ascertained among 81358 participants during the 3 to 14.4 years follow-up. The pooled RR of all-cause mortality risk was 1.57 (95% CI, 1.25 to 1.96, P < 0.001) across the lowest to the normal muscle mass category. The results of meta-regression showed that BMI (P = 0.086) might be sources of heterogeneity between studies. Subgroup analysis showed that low SMI was significantly associated with an increased risk of all-cause mortality in studies with a body mass index (BMI) between 18.5 to 25 (1.34, 95% CI, 1.24-1.45, P<0.001), 25 to 30 (1.91, 95% CI, 1.16-3.15, P = 0.011), and over 30 (2.58, 95% CI, 1.20-5.54 P = 0.015). CONCLUSIONS: Low SMI was significantly associated with the increased risk of all-cause mortality, and the risk of all-cause mortality associated with low SMI was higher in adults with a higher BMI. Low SMI Prevention and treatment might be significant for reducing mortality risk and promoting healthy longevity.

Effects of physical exercise on biomarkers of oxidative stress in healthy subjects: A meta-analysis of randomized controlled trials.

This meta-analysis investigated the effect of physical exercise (PE) on the levels of oxidative biomarkers in randomized controlled trials (RCTs) involving healthy subjects. We searched five databases for articles until May 1, 2023. A random-effect meta-analysis, subgroup analysis, meta-regressions as well as trim and fill method were conducted using STATA 11.0, involving ten articles. According to the results of the meta-analysis, PE had no significant effect on superoxide dismutase (SOD), glutathione peroxidase, and catalase levels. PE induced significant increase in total antioxidant status (standardized mean difference [SMD] 1.53, 95% CI 0.73-2.32), and PE could significantly reduce the level of malondialdehyde (MDA) (SMD -1.11, 95% CI -2.15 to -0.06). Sensitivity analyses and subgroup analyses showed that male participants, body mass index (BMI) <25, exercise duration between 1 and 12 weeks, resistance exercise or multicomponent exercise, and exercise of low or moderate intensity were associated with a significant PE-induced decrease in MDA concentrations. Meta-regression analysis identified the age of the participants as a confounder of the effect of PE on SOD levels. The older age of the subjects was associated in a gradient fashion with incident SOD levels. Further RCTs are required to investigate the optimal PE protocol for people of different ages and BMI as well as the effect of PE on oxidative stress.

Identification of Blast Resistance QTLs Based on Two Advanced Backcross Populations in Rice.

BACKGROUND: Rice blast is an economically important and mutable disease of rice. Using host resistance gene to breed resistant varieties has been proven to be the most effective and economical method to control rice blast and new resistance genes or quantitative trait loci (QTLs) are then needed. RESULTS: In this study, we constructed two advanced backcross population to mapping blast resistance QTLs. CR071 and QingGuAi3 were as the donor parent to establish two BC3F1 and derived BC3F2 backcross population in the Jin23B background. By challenging the two populations with natural infection in 2011 and 2012, 16 and 13 blast resistance QTLs were identified in Jin23B/CR071 and Jin23B/QingGuAi3 population, respectively. Among Jin23B/CR071 population, 3 major and 13 minor QTLs have explained the phenotypic variation from 3.50% to 34.08% in 2 years. And, among Jin23B/QingGuAi3 population, 2 major and 11 minor QTLs have explained the phenotypic variation from 2.42% to 28.95% in 2 years. CONCLUSIONS: Sixteen and thirteen blast resistance QTLs were identified in Jin23B/CR071 and Jin23B/QingGuAi3 population, respectively. QTL effect analyses suggested that major and minor QTLs interaction is the genetic basis for durable blast resistance in rice variety CR071 and QingGuAi3.

Development and evaluation of improved lines with broad-spectrum resistance to rice blast using nine resistance genes.

BACKGROUND: Rice blast disease is a major restriction in rice production. That is usually managed using chemical pesticides, which are expensive in terms of cost and environment hazards. Use of blast-resistance genes to develop resistant varieties may therefore be a more economical and environmentally friendly method for effective control. RESULTS: In this study, we improved the blast resistance of four sterile lines, Y58S, GuangZhan63S (GZ63), C815S and HD9802S, by introgression of 9 cloned broad-spectrum blast resistance genes Pi37, Pit, Pid3, Pigm, Pi36, Pi5, Pi54, Pikm and Pb1. Through molecular marker-assisted selection and backcross breeding, 31 single-gene derived lines and 20 double-gene combination lines were obtained. When infected naturally, single-gene lines with Pigm or Pid3 showed significantly enhanced resistance during whole growth period relative to their recurrent parent. Single-gene lines with Pi37, Pi5, Pit, Pi36, Pi54 or Pikm showed significantly enhanced resistance in some of the four backgrounds. No obviously enhanced resistance was observed in single-gene line with Pb1 for the whole growth period. Compared with recurrent parents, most of the double-gene lines showed improved resistance. Among these double-gene lines, lines with Pi37/Pid3, Pi5/Pi54, Pi54/Pid3 or Pigm/Pi37, exhibited significantly enhanced resistance and observable additive effects. CONCLUSIONS: Two blast resistance genes, Pigm and Pid3, showed significantly enhanced resistance for the whole rice growth period, and six blast resistance genes Pi37, Pi5, Pit, Pi36, Pi54 or Pikm showed significantly enhanced resistance for some of the four backgrounds. Double-gene lines with Pi37/Pid3, Pi5/Pi54, Pi54/Pid3 and Pigm/Pi37 exhibited significantly enhanced resistance and observable additive effects. These lines could be used in rice hybrid and production.

Evaluation and breeding application of six brown planthopper resistance genes in rice maintainer line Jin 23B.

BACKGROUND: The brown planthopper (BPH), an insect species that feeds on rice plants (Oryza sativa L.), is one of the most destructive insect pests of rice. BPH can be controlled with chemical pesticides, but they are expensive in terms of the cost and environmental hazards. Hence, utilization of resistance genes in resistant varieties is considered as a more economical and eco-friendly effective method for control. RESULTS: In this study, six dominant BPH-resistance genes (Bph3, Bph14, Bph15, Bph18, Bph20 and Bph21) were introduced into an elite indica rice cultivar Jin 23B using the marker-assisted selection (MAS) method of breeding. One line combining Bph14 and Bph15 and six single gene introgression lines were used to evaluate the gene effects based on three parameters: seedling and tillering resistance of the rice genotypes, honeydew weight, and BPH survival rate. Among all improved lines, combination of Bph14 and Bph15 had the largest effect in conferring resistance to BPH. Bioassays showed that the order of the gene effects was Bph14/Bph15 > Bph15 ≥ Bph14 ≥ Bph20 ≥ Bph21 ≥ Bph3 > Bph18 > none at the rice seedling stage. The pyramided or single-gene introgression lines showed enhanced resistance relative to the control. Furthermore, field trial data demonstrated that yields of improved Jin 23B lines were similar to the control under BPH-free field conditions. CONCLUSIONS: Each of the BPH resistance genes reduced BPH growth and development, and was effective at both the seedling and tillering growth stages. These lines can be used in rice hybrid and production in China.

The Protective Effect of Baicalin Against Lead-Induced Renal Oxidative Damage in Mice.

Lead (Pb) exposure is a global environmental problem that can deplete body antioxidant enzymes, causing damage to various macromolecules and ultimately cell death. Pb exposure could lead to serious renal damage. Baicalin, a traditional Chinese medicine, could protect against renal injury through inhibition of oxidative stress and apoptosis. This study was designed to investigate the protective efficacy of baicalin against Pb-induced nephrotoxicity in mice and to elucidate the potential mechanisms using animal experiment. The results revealed that baicalin decreased Pb-induced bodyweight loss, declined kidney coefficients, and ameliorated renal function and structure in a dose-dependent manner. Meanwhile, baicalin dose dependently increased Pb-induced activity of SOD and GSH-Px, while the content of MDA in the kidney was decreased. In addition, baicalin enhanced the Bcl-2/Bax ratio associated with apoptosis in the kidney. These data indicated that further investigation of the use of baicalin as a new natural chemopreventive agent against Pd poisoning is warranted.

Mapping and verification of grain shape QTLs based on an advanced backcross population in rice.

Grain shape is a key factor that influences both the appearance quality and grain yield of rice. To clarify the genetic basis of grain shape, an advanced backcross population was developed from the cross of a slender indica variety Jin23B and a round japonica variety QingGuAi, and a total of 10 quantitative trait loci (QTLs) for grain shape were detected over 2 years. Three QTLs, qGW1, qGS3 and qGS7 have large effects on grain shape and were detected in both years. To further validate their effects, the BC4F2 populations of the three QTLs were constructed. The alleles from QingGuAi of qGW1 and qGS7 both greatly increase grain width and the alleles from Jin23B of qGS3 greatly increase grain length. The allele variations of the three QTLs lead to the totally different grain shape of the two rice varieties. Our study provides insights into the genetic bases of grain shape and will promote the improvements of grain quality and yield in rice.

Leonurine exerts anti-inflammatory effect by regulating inflammatory signaling pathways and cytokines in LPS-induced mouse mastitis.

Bovine mastitis is defined as the inflammation of mammary gland and is the most multiple diseases in dairy cattle. There is still no effective treatment now. Leonurine, extracted from Leonurus cardiaca, has been proved to have anti-inflammatory effect. In the present study, we utilized a mouse mastitis model to study the effect of leonurine on LPS-induced mastitis. Leonurine was administered three times during the 24 h after inducing infection in the mammary gland. The results showed that leonurine significantly alleviated LPS-induced histopathological changes, downregulated the levels of pro-inflammatory cytokines tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), upregulated the level of anti-inflammatory cytokine interleukin-10 (IL-10), and inhibited the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). Further study revealed that leonurine inhibited the expression of Toll-like receptor 4 (TLR4) and the activation of nuclear factor-kappaB (NF-κB) and the phosphorylation of p38, extracellular signal-regulated kinase (ERK), and Jun N-terminal kinase (JNK). Therefore, the results demonstrated that leonurine could downregulate the expression of TNF-α, IL-6, iNOS, and COX-2 and upregulate the expression of IL-10 mainly by inhibiting the expression of TLR4 and the activation of NF-κB and the phosphorylation of p38, ERK, and JNK. Leonurine may be a potential agent for mastitis therapy.

Selenium Deficiency Facilitates Inflammation Through the Regulation of TLR4 and TLR4-Related Signaling Pathways in the Mice Uterus.

Selenium (Se) is an essential nutritional trace element that affects the development and function of the reproductive system. Endometritis is a reproductive obstacle disease that can seriously reduce the reproductive capacity of animal. To study the effects of dietary Se deficiency on lipopolysaccharide (LPS)-induced mice endometritis, we generated a model of LPS-induced mice endometritis. The Se content in uterine tissues was detected by fluorescence spectrophotometry. The levels of tumor necrosis factor-α (TNF-α), interleukin (IL)-1ß, and IL-6 were measured by enzyme-linked immunosorbent assay (ELISA) and quantitative real-time polymerase chain reaction (qRT-PCR). The extent of phosphorylation of IκBα, NF-κB p65, ERK, JNK, and p38 and the expression of Toll-like receptor 4 (TLR4) were detected with Western blots. The TLR4 messenger RNA (mRNA) was analyzed with qRT-PCR. The results indicated that dietary Se intake significantly influenced Se levels in uterine tissues. The Se-deficient mice model was successfully replicated, and Se deficiency exacerbated uterine tissue histopathology; increased the expression of TNF-α, IL-1ß, and IL-6; facilitated the activation of TLR4; and enhanced the phosphorylation of IκBα, p65, ERK, JNK, and p38 in LPS-induced mice endometritis. Also, the effects were inhibited by a supplement of Se. In conclusion, our studies demonstrated that Se deficiency makes mice uterus more prone to inflammation. An appropriate Se supplement could enhance the immune condition of the uterus.

Selenium inhibits LPS-induced pro-inflammatory gene expression by modulating MAPK and NF-κB signaling pathways in mouse mammary epithelial cells in primary culture.

Mastitis is characterized by an inflammation of the mammary gland of dairy animals and humans; this condition is one of the major causes of economic losses in dairy industries. Selenium (Se), a biological trace element, modulates the functions of many regulatory proteins in signal transduction and provides advantages for animals with inflammatory diseases, including mastitis. The current study aimed to assess the protective effects and the active mechanism of Na(2)SeO(3) against lipopolysaccharide (LPS)-induced inflammation in mouse mammary epithelial cells (MMECs). Our results showed that LPS-induced expressions of cyclooxygenase-2 and tumor necrosis factor-α significantly decreased after Se was supplemented to Se-deficient MMECs. Na(2)SeO(3) also suppressed LPS-induced nuclear factor-κB activation, inhibitory kappa B degradation, and ERK, JNK, and P38 phosphorylation in a dose-dependent manner. These results suggested that Se functions as an anti-inflammatory agent in mastitis.

Stevioside inhibits inflammation and apoptosis by regulating TLR2 and TLR2-related proteins in S. aureus-infected mouse mammary epithelial cells.

Stevioside is a natural sweetener that is commonly used in traditional medicine and as a food additive. The object of this study was to investigate the anti-inflammatory and anti-apoptosis function of stevioside and the possible molecular mechanisms for such activity in Staphylococcus aureus (S. aureus)-infected mouse mammary epithelial cells (MMECs). The cells were treated with varying doses of stevioside before infection with S. aureus. The live/dead cells were detected by immunofluorescence microscopy. The pro-inflammatory cytokines were determined by ELISA. The mRNA of TLR2 and proteins related to NF-κB, MAPK and apoptosis were analyzed by q-PCR. The relative protein expression levels were determined by Western blot. The results indicated that stevioside inhibited the mRNA and protein expression of TNF-α, IL-6 and IL-1ß dose-dependently in S. aureus-stimulated MMECs. Stevioside suppressed the S. aureus-induced expression of TLR2 and proteins of the NF-κB and MAPK pathways as well as apoptosis. The mRNA levels of IκBα, p38, ERK, JNK, p65, caspase-3 and Bax were not influenced by the stevioside treatment. Stevioside exerts anti-inflammatory and anti-apoptotic properties by inhibiting the release of cytokines and the activation of TLR2 and proteins of the NF-κB and MAPK signaling pathways, as well as caspase-3 and Bax.

Stevioside plays an anti-inflammatory role by regulating the NF-κB and MAPK pathways in S. aureus-infected mouse mammary glands.

Mastitis is an inflammatory disease caused by microbial infection. Staphylococcus aureus is one of the primary bacteria responsible for mastitis. Stevioside is isolated from Stevia rebaudiana and is known to have therapeutic functions. This study was designed to evaluate the effects of stevioside in a mouse model of S. aureus-induced mastitis. In this study, the mouse mammary gland was infected with S. aureus to induce the mastitis model. The stevioside was administered intraperitoneally after the S. aureus infection was established. Hematoxylin-eosin (HE) staining, ELISA, Western blot, and q-PCR methods were used. The results show that stevioside significantly reduced the inflammatory cell infiltration and the levels of TNF-α, IL-1ß, and IL-6 and the respective expression of their messenger RNAs (mRNAs). Further studies revealed that stevioside downregulated the TLR2, NF-κB, and (mitogen-activated protein kinase) MAPK signaling pathways in the S. aureus-infected mouse mammary gland. Our results demonstrate that stevioside reduced the expression of TNF-α, IL-1ß, and IL-6 by inhibiting the phosphorylation of proteins in the NF-κB and MAPK signaling pathways dose-dependently, but that their mRNA expression was not obviously changed.

Geniposide plays an anti-inflammatory role via regulating TLR4 and downstream signaling pathways in lipopolysaccharide-induced mastitis in mice.

Geniposide is a medicine isolated from Gardenia jasminoides Ellis, which is a traditional Chinese herb that is widely used in Asia for the treatment of inflammation, brain diseases, and hepatic disorders. Mastitis is a highly prevalent and important infectious disease. In this study, we used a lipopolysaccharide (LPS)-induced mouse mastitis model and LPS-stimulated primary mouse mammary epithelial cells (mMECs) to explore the anti-inflammatory effect and the mechanism of action of geniposide. Using intraductal injection of LPS as a mouse model of mastitis, we found that geniposide significantly reduced the infiltration of inflammatory cells and downregulated the production of tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), and interleukin-6 (IL-6). To further investigate the anti-inflammatory mechanism, we used LPS-stimulated mMECs as an in vitro mastitis model. The results of enzyme-linked immunosorbent assay (ELISA) and quantitative real-time polymerase chain reaction (qRT-PCR) showed that geniposide inhibited the expression of TNF-α, IL-1ß, and IL-6 in a dose-dependent manner. Western blot analysis demonstrated that geniposide could suppress the phosphorylation of inhibitory kappa B (IκBα), nuclear factor-κB (NF-κB), p38, extracellular signal-regulated kinase (ERK), and c-Jun N-terminal kinase (JNK). Geniposide also inhibited the expression of toll-like receptor 4 (TLR4) in the LPS-stimulated mMECs. In conclusion, geniposide exerted its anti-inflammatory effect by regulating TLR4 expression, which affected the downstream NF-κB and mitogen-activated protein kinase (MAPK) signaling pathways. Thus, geniposide may be a potential drug for mastitis therapy.