Integrated analysis of transcriptome and metabolome reveals the regulatory mechanism of largemouth bass (Micropterus salmoides) in response to Nocardia seriolae infection.

Nocardia seriolae is a severe bacterial pathogen that has seriously affected the development of aquaculture industry. Largemouth bass (Micropterus salmoides) is a commercially significant freshwater fish that suffers a variety of environmental threats, including bacterial pathogens. However, the immune responses and metabolic alterations of largemouth bass to N. seriolae infection remain largely unclear. We discovered that N. seriolae caused pathological alterations in largemouth bass and shifted the transcript of immune-related and apoptotic genes in head kidney after infection. To answer the aforementioned question, a combined transcriptome and metabolome analysis was employed to explore the alterations in genes, metabolites, and metabolic pathways in largemouth bass following bacterial infection. A total of 3579 genes and 1929 metabolites are significant differentially changed in the head kidney post infection. In response to N. seriolae infection, host modifies the PI3K-Akt signaling pathway, TCA cycle, glycolysis, and amino acid metabolism. The integrated analysis of transcriptome and metabolome suggested that with the arginine metabolism pathway as the core, multiple biomarkers (arg gene, arginine) are involved in the antibacterial and immune functions of largemouth bass. Thus, we hypothesized that arginine plays a crucial role in the immune responses of largemouth bass against N. seriolae infection, and increasing arginine levels suitably is beneficial for the host against bacterial infection. Our results shed light on the regulatory mechanism of largemouth bass resistance to N. seriolae infection and contributed to the development of more effective N. seriolae resistance strategies.

Effects of Different Static Progressive Stretching Durations on Range of Motion, Myofibroblasts, and Collagen in a Posttraumatic Knee Contracture Rat Model.

OBJECTIVE: The purpose of this study was to investigate the effects of different durations of static progressive stretching (SPS) on posttraumatic knee contracture in rats, including range of motion (ROM), gait analysis, myofibroblast proliferation, and collagen regulation. METHODS: The posttraumatic knee contracture model was established, and male Wistar rats were randomly divided into the 20-minute SPS treatment, 30-minute SPS treatment (S30), 40-minute SPS treatment, untreated, immobilization, and control groups. At Week 1, 2, and 4 of treatment intervention, joint ROM and gait were measured and compared. Knee joint samples stained with hematoxylin and eosin and Masson trichrome were used to observe alterations in pathological structures. Collagen density and cell numbers in the posterior joint capsule were used to assess joint capsule fibrosis and inflammation. Immunohistochemistry was used to detect type I collagen and α-smooth muscle actin expression. RESULTS: The S30 group improved the most; ROM, stance, mean intensity, print area, and stride length were 115 (SD = 5) degrees, 0.423 (SD = 0.074) seconds, 156.020 (SD = 7.952), 2.116 (SD = 0.078) cm2, and 11.758 (SD = 0.548) cm, respectively. The numbers of myofibroblasts, fibroblasts, and inflammatory cells decreased, and collagen proliferation was significantly suppressed in the S30 group compared with the other groups. CONCLUSION: S30 significantly improved posttraumatic knee contracture in rats, with reduced type I collagen and α-smooth muscle actin expression, decreased the numbers of myofibroblasts and inflammatory cells, suppressed fibrotic and inflammatory changes in the joint capsule, and increased joint mobility. This study provided basic evidence for an optimal standard-of-care treatment approach for posttraumatic knee joint contracture in rats, which may have significance for humans.

[The Therapeutic Effect and Mechanism of Static Progressive Stretching in Different Durations on Traumatic Knee Contracture in Rats].

OBJECTIVE: To investigate the effect and mechanism of static progressive stretching (SPS) in different durations on traumatic knee contracture in rats. METHODS: Seventy male Wistar rats were randomly divided into three groups, including surgical modeling group ( n=50), control group (CON, no surgery, no treatment, n=10) and trauma without immobilization group (TRA, no treatment, n=10). The knee contracture model was established, and 50 surgical modeling rats were randomly divided into five groups including static progressive stretching treatment for 20 minutes group (S20 min, n=10), treatment for 30 minutes group (S30 min, n=10), treatment for 40 minutes group (S40 min, n=10), untreatment group (UNT, no SPS, n=10) and modeling group (MOD, n=10, euthanized after immobilization for histological staining and Western blot). Individuals in the S20 min, S30 min, and S40 min groups were anesthetized and submitted to SPS. One treatment session took place every other day. A total of 8 sessions were given till the final treatment session on the day 16. On the day 0, 8, and 16 of intervention, the range of joint motion (ROM) and gait analysis were measured and compared. After the ROM measurements and gait analysis, the rats were euthanized on the day 16 and the samples were stained with HE and Masson methods. The changes of pathological organization were observed. Western blot was used to detect the expressions of transforming growth factor-ß1 (TGF-ß1) and interleukin-6 (IL-6). RESULTS: ① ROM：the ROM of S30 min group recovered similar to that of the S20 min and S40 min groups after 8 days of treatment ( P>0.05), and was the best among all the surgical modeling groups after 16 d of treatment ( P<0.05). The ROM of S20 min, S30 min and S40 min groups significantly improved on the day 8 and day 16 comparing with that on day 0 ( P<0.01). ② Gait analysis: the stands in the S30min group improved best on the day 8 and day 16 ( P<0.05) , and better than that on day 0 ( P<0.05). The stride length of the S30 min group progressed similar to that of the S40 min group on the day 8 ( P>0.05), and there was no difference among three groups on the day 16 ( P>0.05). The stride length of the S30 min group appeared to recover more quickly on the day 8 ( P<0.05), and those of S20 min and UNT groups recovered significantly on the day 16 ( P<0.05). In addition, the swings in the S30 min group improved best ( P<0.05), and it appeared to recover better on the day 16 ( P<0.05). There was no statistical difference in terms of the swing speed among the four surgical modeling groups on the day 8 ( P>0.05). The swing speed of the S30min group increased most than those of the other three groups ( P<0.05), and it was much better on the day 8 and day 16 comparing with that on the day 0 ( P<0.05 ). ③ HE and Masson staining: the fibrosis and inflammation of the S30min group were significantly suppressed comparing to the other groups on the day 16. ④ Western blot: The protein expression levels of TGF-ß1 and IL-6 were significantly lower than those in the other intervention groups including the S20 min, S40 min and UNT groups on the day 16 ( P<0.05). CONCLUSION: Static progressive stretching treatment for 30 min could significantly improve the traumatic knee contracture in rats. The mechanism may be that the SPS decreased the expressions of TGF-ß1 and IL-6, reduced the adhesion and inflammation of joint capsule. Therefore it relieved the pain and increased the joint mobility by reconstructing the structure of the capsule and suppressing the fibrotic changes.

[Cardiotoxicity study of Shenfu compatibility in rats based on metabonomics].

To research the effect of Ginseng Radix et Rhizoma and Aconiti Lateralis Radix Praeparata compatibility on cardiac toxicity in rats by UPLC-Q-TOF/MS, and explore the endogenous markers and molecule mechanism. Different compatibility of Shenfu decoction were given to male Wistar rats at dosage of 20 g · kg(-1) for 7 days, collected the serum, and analyze the endogenous metabolites effected by Shenfu formulation by principal component analysis and partial least-squares analysis. Results showed that content of glutathione, phosphatidylcholine and citric acid decreased in mixed-decoction group, while ascorbic acid, uric acid, D-galactose, tryptophan, L-phenylalanine increased. The results showed cardiac toxicity of Aconiti Lateralis Radix Praeparata in Shenfu mixed-decoction. Shenfu co-decoction group showed a similar or weaker trend compared with control group, but most of them do not have a statistically significant. The results indicated the scientific basis of Shenfu compatibility by comparison of co-decoction group with mixed-decoction group. Shenfu compatibility can reduce cardiac toxicity induced by Aconiti Lateralis Radix Praeparata, and citric acid, glutathione, phosphatidyl choline, uric acid might be regarded as potential markers of cardiotoxicity.

Serum Pharmacochemistry Analysis Using UPLC-Q-TOF/MS after Oral Administration to Rats of Shenfu Decoction.

The purpose of this study was to study the serum pharmacochemistry of SFD as well as the material basis through analyzing the constituents absorbed in blood. The SFD was orally administrated to Wistar rats at 20 g·kg(-1), and Ultra Performance Liquid Chromatography (UPLC) fingerprints of SFD were created. Serum samples were collected for analysis, and further data processing used MarkerLynx XS software. 19 ginsenosides and 16 alkaloids were detected in SFD. The absorption of alkaloids (mainly monoester diterpenoid alkaloids) increased when Aconitum carmichaeli Debx. was combined with Panax ginseng, while the ginsenosides remained stable. Diester diterpenoid alkaloids were not present in the serum samples. A suitable serum pharmacochemistry method was successfully established to study pharmacological effects and potential improvements in formulation. This may also be useful for toxicity reduction. We suspect that the increased absorption of the monoester diterpenoid alkaloids from the mixture of Panax and Radix, compared to the Panax only extract, may be the reason for the combination of the two herbs in popular medicine formulas in China.