Catalpol protects mice against Lipopolysaccharide/D-galactosamine-induced acute liver injury through inhibiting inflammatory and oxidative response

Effects of Catalpol from Rehmannia glutinosa Extract on Skin Flaps

BACKGROUND

Flaps are commonly used for repairing tissues and wounds in surgery. However, various factors can cause postoperative necrosis in these flaps. Catalpol is a bioactive component in extracts from Rehmannia glutinosa , which has pharmacologic characteristics that may improve flap survival.

METHODS

The experiments were performed in 36 male Sprague-Dawley rats divided into three groups: control, low-dose catalpol, and high-dose catalpol. The flap survival rate, neutrophil density, microvessel density, superoxide dismutase, and malondialdehyde levels were measured; histopathologic analysis was performed 7 days after surgery. Blood flow was measured by laser Doppler flowmetry and lead oxide-gelatin angiography. The levels of vascular endothelial growth factor, toll-like receptor 4, nuclear factor-kappa B, tumor necrosis factor-α, interleukin (IL)-6, nod-like receptor 3, cysteinyl aspartate specific proteinase-1 (caspase-1), IL-1β, and IL-18 were determined by immunohistochemistry.

RESULTS

Catalpol treatment increased flap survival, reduced neutrophil recruitment and release, decreased malondialdehyde levels, and increased superoxide dismutase levels; thus, it effectively reduced oxidative stress, up-regulated the expression of vascular endothelial growth factor, and increased microvessel density. Laser Doppler flowmetry and lead oxide-gelatin angiography showed that catalpol treatment improved angiogenesis. Immunohistochemical analyses showed that catalpol inhibited the production of inflammatory factors, such as tumor necrosis factor-α and IL-6, by down-regulating toll-like receptor 4 and nuclear factor-κB. Furthermore, catalpol reduced cell pyroptosis by inhibiting the production of nod-like receptor 3 inflammasomes, thereby down-regulating the release of IL-1β and IL-18.

CONCLUSION

Catalpol can improve the rate of flap survival.

CLINICAL RELEVANCE STATEMENT

The research verified that the Rehmannia extract catalpol, through angiogenesis, inflammatory response, ischemia-reperfusion injury, and pyroptosis-related pathways, effectively improved the flap survival rate, which will provide new ideas for clinical medication.

Catalpol ameliorates inflammation and oxidative stress via regulating Sirt1 and activating Nrf2/HO-1 signaling against acute kidney injury

BACKGROUND

Septic acute kidney injury (SAKI) is usually caused by sepsis. It has been shown that catalpol (Cat) impairs sepsis-evoked organ dysfunction to a certain degree. The current work aims to evaluate the protective effects of Cat on SAKI and potential mechanisms in vivo and in vitro.

METHODS

SAKI cellular and murine model were set up using lipopolysaccharide (LPS) in vitro and in vivo. Cell apoptosis in cells was determined by TUNEL assay. Levels of inflammatory cytokines were detected by enzyme-linked immunosorbent assay (ELISA). The levels of the markers of oxidative injury were evaluated by corresponding commercial kits. Protein levels were assayed via western blotting and immunohistochemistry (IHC) staining.

RESULTS

The results demonstrated that LPS upregulated TNF-α, IL-6, and malondialdehyde levels, and downregulated superoxide dismutase, whereas Cat treated cells have the opposite results. Functional assays displayed that Cat remarkably reversed the LPS-challenged damage as the impairment of TNF-α and IL-6 levels, oxidative stress, and the apoptosis in HK-2 cells. Moreover, knockdown of Sirtuin 1 (Sirt1) counteracted the suppressive impact of Cat on LPS-triggered inflammatory response, oxidative stress, and renal damage. Further, Cat elevated Sirt1 expression and activated the Nrf2/HO-1 signaling in LPS-engendered SAKI in vivo and in vitro.

CONCLUSION

Our study clearly proved that Cat protected against LPS-induced SAKI via synergic antioxidant and anti-inflammatory actions by regulating Sirt1 and Nrf2/HO-1 signaling pathways.

Beneficial Effects of Catalpol Supplementation during In Vitro Maturation of Porcine Cumulus-Oocyte Complexes

Oxidative stress degrades oocytes during in vitro maturation (IVM). Catalpol, a well-known iridoid glycoside, exhibits antioxidant, anti-inflammatory, and antihyperglycemic effects. In this study, catalpol supplementation was tested on porcine oocyte IVM and its mechanisms. Corticalgranule (GC) distribution, mitochondrial function, antioxidant capacity, DNA damage degree, and real-time quantitative polymerase chain reaction were used to confirm the effects of 10 μmol/L catalpol in the maturation medium during IVM. Catalpol treatment significantly increased the first-pole rate and cytoplasmic maturation in mature oocytes. It also increased oocyte glutathione (GSH), mitochondrial membrane potential and blastocyst cell number. However, DNA damage as well as reactive oxygen species (ROS) and malondialdehyde (MDA) levels. Mitochondrial membrane potential and blastocyst cell number were also increased. Thus, the supplementation of 10 μmol/L catalpol in the IVM medium improves porcine oocyte maturation and embryonic development.

Catalpol alleviates myocardial ischemia reperfusion injury by activating the Nrf2/HO-1 signaling pathway

PURPOSE

Myocardial ischemia/reperfusion injury (MI/RI) is a major problem in the clinical treatment of ischemic cardiomyopathy, and its specific underlying mechanisms are complicated and still unclear. A number of studies have indicated that the nuclear factor erythroid 2-related factor 2 (Nrf2)/heme oxidase-1(HO-1) signaling pathway might serve as an important target for the management of MI/RI. Catalpol is a kind of iridoid glucoside that has been found to exhibit diverse anti-inflammatory and antioxidant properties. This study was aimed at investigating the role of Catalpol in targeting MI/RI and its related mechanisms in an oxygen-glucose deprivation/reoxygenation (OGD/R) model in vitro and a preclinical ischemia/reperfusion (I/R) model.

METHODS

This study using both in vitro and in vivo models investigated the possible role and underlying mechanisms used by Catalpol for modulating of MI/RI. The potential effects of Catalpol on the viability of cardiomyocytes were measured by cell counting kit-8 (CCK-8) assays. The phenotypes of myocardial injury, oxidative stress and inflammation markers were measured by western blot, immunofluorescence, enzyme-linked immunosorbent assay (ELISA) etc. Nrf2/HO-1 signaling pathway was detected by immunofluorescence and western blot analysis.

RESULTS

We found that Catalpol significantly suppressed the process of MI/RI and protected OGD/R-treated cardiomyocytes by inhibiting the various markers of inflammation and suppressing oxidative stress. Additionally, mechanistically it was also demonstrated that Catalpol could effectively activate Nrf2/HO-1 signaling pathway to suppress the damage caused by inflammation and oxidative stress in MI/RI.

CONCLUSION

In summary, the findings suggest that Catalpol exerted significant cardioprotective effects following myocardial ischemia, possibly through the activation of the Nrf2/HO-1 signaling pathway.

Metabolism of Du Zhong Formula in rats using UPLC-Q-TOF/MS

Du Zhong Formula (DZF), a traditional Chinese medicine formula derived from BeiJiQianJinYaoFang, is used to treat kidney deficiency and lumbago. In this study, ultra-high-performance liquid chromatography quadrupole time-of-flight mass spectrometer (UPLC-Q-TOF/MS) technique combined with pattern recognition analysis was applied for analysis of metabolic profiles of the bioactive components of the DZF in rat biological samples. In this experiment, a total of 73 compounds, including 53 prototype components and 20 metabolites, were identified tentatively in vivo compared with blank urine, plasma, feces, and cerebrospinal fluid (CSF). The prototype ingredients in DZF include terpenoids, gingerols, phenylpropanoids, alkaloids, phenanthrenes, bibenzyls, organic acids, and other ingredients. The metabolic pathways of DZF involved reduction, demethylation, hydroxylation, desugarization, deoxygenation, glucuronidation, sulfation, and methylation. The proposed method could develop an integrated template approach to analyze screening and identification of the bioactive components in plasma, urine, feces, and CSF after oral administration of herb medicines. Additionally, this investigation might provide helpful chemical information for further pharmacology and activity mechanism of DZF.

Effects of Bushen-Tiaojing-Fang on the pregnancy outcomes of infertile patients with repeated controlled ovarian stimulation

Bushen-Tiaojing-Fang (BSTJF) is commonly used to treat infertility. This study investigated the effects of BSTJF on the pregnancy outcomes of patients with repeated controlled ovarian stimulation (COS), on mitochondrial function, and on oxidative stress in ovarian granulosa cells (GCs) and follicular fluid (FF). The samples and clinical data of 97 patients, including 35 in the control group, 29 in the placebo group and 33 in the BSTJF group, were collected for this study. The mitochondrial ultrastructure, ATP content, mitochondrial DNA (mtDNA) number, 8-hydroxy-2-deoxyguanosine (8-OHdG), Mn-superoxide dismutase (Mn-SOD), glutathione peroxidase (GSH-Px) activity levels, and mRNA expression levels of Mn-SOD, GSH-Px, and nuclear factor erythroid-derived factor 2-related factor 2 (Nrf2) were analyzed. The high-grade embryo (P < 0.001), implantation (P = 0.033), and clinical pregnancy (P = 0.031) rates, as well as the ATP content (P = 0.014), mtDNA number (P = 0.035), GSH-Px activity (P = 0.004 in GCs and P = 0.008 in FF) and mRNA expression levels (P = 0.019), were significantly lower in the placebo group than in the control group, whereas the 8-OHdG content was significantly (P = 0.006 in FF) higher in the placebo group than in the control group. Compared with those in the placebo group, the high-grade embryo rate (P = 0.007), antioxidant enzyme activity (P = 0.037 and 0.036 in Mn-SOD; P = 0.047 and 0.030 in GSH-Px) and mRNA level (P < 0.001 in Nrf2, P = 0.039 in Mn-SOD and P = 0.002 in GSH-Px) were significantly higher in the BSTJF group, as were changes in mitochondrial ultrastructure, ATP (P = 0.040) and mtDNA number (P = 0.013). In conclusion, BSTJF can improve oxidative stress in patients with repeated COS and pregnancy outcomes.

Catalpol Protects Against Spinal Cord Injury in Mice Through Regulating MicroRNA-142-Mediated HMGB1/TLR4/NF-κB Signaling Pathway

Background: Spinal cord injury (SCI) is a devastating condition that leads to paralysis, disability and even death in severe cases. Inflammation, apoptosis and oxidative stress in neurons are key pathogenic processes in SCI. Catalpol (CTP), an iridoid glycoside extracted from Rehmannia glutinosa, has many pharmacological activities, such as anti-inflammatory, anti-oxidative and anti-apoptotic properties.

Purpose: Here, we investigated whether CTP could exert neuroprotective effects against SCI, and explored the underlying mechanism involved.

Methods: SCI was induced by a weight-drop device and treated with CTP (10 mg and 60 mg/kg). Then the locomotor function of SCI mice was evaluated by the BBB scores, spinal cord edema was measured by the wet/dry weight method, oxidative stress markers and inflammatory factors were detected by commercial kits and neuronal death was measured by TUNEL staining. Moreover, the microRNA expression profile in spinal cords from mice following SCI was analyzed using miRNA microarray. In addition, reactive oxygen species (ROS) generation, inflammatory response and cell apoptosis were detected in murine microglia BV2 cells under oxygen-glucose deprivation (OGD) and CTPtreatment.

Results: Our data showed that CTP treatment could improve the functional recovery, as well as suppress the apoptosis, alleviate inflammatory and oxidative response in SCI mice. In addition, CTP was found to be up-regulated miR-142 and the protective effects of CTP on apoptosis, inflammatory and oxidative response may relate to its regulation of HMGB1/TLR4/NF-κB pathway through miR-142.

Conclusion: Our findings suggest that CTP may protect the spinal cord from SCI by suppression of apoptosis, oxidative stress and inflammatory response via miR-142/HMGB1/TLR4/NF-κB pathway.

Inhibition of Bruton tyrosine kinase by acalabrutinib dampens lipopolysaccharide/galactosamine-induced hepatic damage

Bruton tyrosine kinase (BTK) sits at the crossroads of adaptive and innate immunities. Nevertheless, the detailed role of BTK activation in hepatic inflammatory disorders is still elusive to date. Accordingly, we investigated the impact of blocking BTK activation by acalabrutinib (ACB) on lipopolysaccharide/galactosamine (LPS/D-GaIN)-induced deleterious manifestations in the liver. This was achieved by pretreating mice with ACB (6, 12 or 24 mg/kg, oral) 2 h before challenge with LPS/D-GaIN (70 μg/kg and 700 mg/kg, respectively, i.p.) for 6 h. The results showed that ACB (6 and 12 mg/kg) (i) curbed LPS/D-GaIN-induced rise in biochemical (serum ALT, AST and LDH) and histological (necrosis, degeneration and congestion scores) indices of hepatocellular injury; (ii) attenuated LPS/D-GaIN-induced elevation in parameters of hepatocellular apoptosis (cleaved caspase 3) and proliferation (PCNA); and (iii) importantly, mitigated LPS/D-GaIN-induced recruitment and infiltration of the inflammatory cells to the liver evidenced by lowering elevated serum MCP-1 concentration and hepatic F4/80 immunostaining. These effects were linked to ACB dose-dependent inhibition of NF-κB nuclear translocation that subsequently reduced LPS/D-GaIN-mediated release of TNF-α, IL-1β and IL-22 in the blood circulation. However, a dose of 12 mg/kg of ACB elevated the hepatic TNF-α, IL-1β and IL-22 concentrations that arose from a compensatory activation of ERK and JNK. Inhibition of BTK also attenuated LPS/D-GaIN-induced overexpression of CD98, which is another contributor alongside cytokines for monocyte recruitment. Therapeutically, targeting BTK by ACB is an efficient approach for hitting multiple points with one agent that can dampen hepatocellular injury, death, immune cell recruitment and inflammation cascade.

Treatment with catalpol protects against cisplatin-induced renal injury through Nrf2 and NF-κB signaling pathways

Cisplatin (CP) is one of the most widely used chemotherapy drugs for cancer treatment, but it often leads to nephrotoxicity. It is well known that catalpol exhibits antioxidant and anti-inflammatory functions, thus the present study aimed to investigate the potential protective effects of catalpol on CP-induced kidney injury in rats, in addition to determining the underlying mechanisms. Sprague-Dawley rats were treated with 25, 50 or 100 mg/kg catalpol for two days, injected with 20 mg/kg cisplatin and catalpol on day 3 and sacrificed on day 4. The histological analysis of isolated kidney tissues was performed using hematoxylin and eosin staining, cleaved caspase-3 expression levels were analyzed using western blotting and the expression levels of inflammatory cytokines in the tissues, including tumor necrosis factor α (TNF-α), interleukin (IL)-1β, IL-6, IL-8, IL-10 and inducible nitric oxide synthase (iNOS) were evaluated using ELISAs. Furthermore, the mRNA and protein expression levels of nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygenase 1 (HO-1), kelch-like ECH-associated protein 1 (Keap1), NF-κB and inhibitory κB (IκB) were determined using reverse transcription-quantitative PCR and western blotting, respectively. The results revealed that the treatment with catalpol prevented the histopathological injury and renal dysfunction caused by CP. In addition, catalpol significantly suppressed the CP-induced apoptosis of tubular cells, inhibited the CP-induced upregulation of TNF-α, IL-1β, IL-6, IL-8 and iNOS and promoted the production of the anti-inflammatory cytokine IL-10. Additionally, the mRNA and protein expression levels of Nrf2, HO-1 and IκB in the kidney tissues were increased, whereas the expression levels of Keap1 and NF-κB were significantly decreased following the treatment with catalpol. In conclusion, these results suggested that catalpol may inhibit CP-induced renal injury and suppress the associated inflammatory response through activating the Nrf2 and inhibiting the NF-κB signaling pathways, respectively.

Protective effects of catalpol on mitochondria of hepatocytes in cholestatic liver injury

Cholestasis, which is caused by the obstruction of bile flow, can lead to rapid organ injury, cell apoptosis and necrosis of hepatocytes, and may eventually develop into fibrosis and cirrhosis. Oxidative stress and mitochondrial dysfunction are the key pathogenic signs of hepatic cholestasis. Catalpol has pharmacological activities, including antioxidative and anti-inflammatory effects, and may relieve mitochondrial damage and restore mitochondrial membrane potential. However, the potential roles and mechanisms of catalpol in cholestasis-induced liver injury are not clear. In the present study, liver function-related indexes were measured in the serum of mice by commercial kits. In addition, levels of serum inflammatory factors were detected by ELISA. Hematoxylin and eosin staining was performed to observe histopathological changes, and mitochondrial membrane potential was detected using JC-1 staining. Mitochondrial adenosine triphosphate (ATP), reactive oxygen species (ROS) and malondialdehyde levels were determined using a luciferase reporter kit, flow cytometry and a thiobarbituric acid reactive substance assay kit, respectively. Western blotting was performed to detect the expression levels of apoptosis-related proteins in liver tissues. The findings revealed that catalpol reduced liver damage caused by cholestasis, improved the mitochondrial membrane potential, and increased the ATP content and glutathione content of cholestasis model mice. Moreover, catalpol also reduced the ROS level, inhibited lipid peroxidation, and regulated oxidative stress and apoptotic protein expression. Thus, the present study preliminarily confirmed that catalpol can reduce liver injury in a mouse model of cholestasis through inhibiting oxidative stress and enhancing mitochondrial membrane potential.

Repeated stretch-shortening contraction of the triceps surae attenuates muscle atrophy and liver dysfunction in a rat model of inflammation

NEW FINDINGS

What is the central question of this study? Is stretch-shortening contraction effective to attenuate skeletal muscle atrophy and hepatic dysfunction in a rat model of peptidoglycan-polysaccharide (PG-PS)-induced inflammation (PG-PS rat)? What are the main findings and their importance? Stretch-shortening contraction attenuates skeletal muscle atrophy in the trained leg and increases circulating interleukin-10 in PG-PS rats. Stretch-shortening contraction also ameliorates liver dysfunction in PG-PS rats, possibly via increased blood interleukin-10. These findings are important because they suggest that stretch-shortening contraction is effective to maintain liver function in addition to exercised skeletal muscle mass.

ABSTRACT

Stretch-shortening contraction (SSC) is an effective modality to improve skeletal muscle mass. However, the beneficial effects of SSC in the presence of chronic inflammation remain unclear. Here, we imposed five SSC sessions unilaterally on the triceps surae in young female Lewis rats. Rats were injected with vehicle or peptidoglycan-polysaccharide (PG-PS) to induce long-lasting inflammation. The PG-PS reduced gastrocnemius muscle mass in both legs, but that of the SSC-trained leg was significantly greater than that of the contralateral leg. Circulating pro-inflammatory cytokines, such as IL-1β, were significantly increased by PG-PS injection, even if carrying out SSC. The circulating anti-inflammatory cytokine IL-10 increased with SSC in both healthy and inflammatory conditions. Stretch-shortening contraction also prevented increases in serum aspartate aminotransferase activity and plasma free phenylalanine concentration induced by PG-PS, in comparison to the control resistance exercise consisting of isometric contractions. Moreover, aspartate aminotransferase and phenylalanine concentrations demonstrated a significant and negative correlation with IL-10/IL-1β values (r = -0.61, P = 0.017, and r = -0.66, P = 0.008, respectively). These results suggest that SSC training is effective to reduce both muscle atrophy and the hepatic dysfunction induced by PG-PS, mediated, at least in part, through an increase in circulating IL-10.

Catalpol‑mediated microRNA‑34a suppresses autophagy and malignancy by regulating SIRT1 in colorectal cancer

Colorectal cancer (CRC) is one of the most common digestive tract tumors worldwide. Catalpol exerts inhibitory effects on the progression of several cancer types by regulating microRNAs (miRs). However, the precise role and carcinostatic mechanism of catalpol on CRC cells are poorly understood which limits the application of catalpol treatment. In the present study, miR-34a and sirtuin 1 (SIRT1) expression levels were detected in CRC tissues and CRC cell lines by RT-qPCR. Computational software analysis, luciferase assays and western blotting were used to demonstrate the downstream target of miR-34a in CRC cells. Effects of catalpol on cell viability, apoptosis, autophagic flux and the miR-34a/SIRT1 axis in the CRC cells were assessed by CCK-8 assay, flow cytometry, electron microscopy and western blotting, respectively. Whether the miR-34a/SIRT1 axis participated in catalpol-mediated autophagy and apoptosis was investigated. The effects of catalpol on the miR-34a/SIRT1 axis and malignant behavior were evaluated in a rat model of azoxymethane (AOM)-induced CRC. It was revealed that miR-34a expression levels were significantly decreased while SIRT1 was overexpressed in most of the CRC tissues and all the CRC cell lines. Clinically, a low level of miR-34a was correlated with poor clinicopathological characteristics in CRC patients. Catalpol reduced cell viability, suppressed autophagy, promoted apoptosis, and regulated the expression of SIRT1 by inducing miR-34a in vitro and in vivo. The autophagy-inhibiting effect of catalpol may be a mechanism to promote apoptosis of CRC cells. miR-34a mimic transfection resulted in autophagy-suppressive activity similar to that of catalpol, while the miR-34a inhibitor attenuated the antiautophagic effects of catalpol. In conclusion, miR-34a is involved in regulating catalpol-mediated autophagy and malignant behavior by directly inhibiting SIRT1 in CRC.

Radix Rehmanniae and Corni Fructus against Diabetic Nephropathy via AGE-RAGE Signaling Pathway

BACKGROUND AND AIMS

Radix Rehmanniae and Corni Fructus (RC) have been widely applied to treat diabetic nephropathy (DN) for centuries. But the mechanism of how RC plays the therapeutic role against DN is unclear as yet.

METHODS

The information about RC was obtained from a public database. The active compounds of RC were screened by oral bioavailability (OB) and drug-likeness (DL). Gene ontology (GO) analysis was performed to realize the key targets of RC, and an active compound-potential target network was created. The therapeutic effects of RC active compounds and their key signal pathways were preliminarily probed via network pharmacology analysis and animal experiments.

RESULTS

In this study, 29 active compounds from RC and 64 key targets related to DN were collected using the network pharmacology method. The pathway enrichment analysis showed that RC regulated advanced glycosylation end product (AGE-) RAGE and IL-17 signaling pathways to treat DN. The animal experiments revealed that RC significantly improved metabolic parameters, inflammation renal structure, and function to protect the kidney against DN.

CONCLUSIONS

The results revealed the relationship between multicomponents and multitargets of RC. The administratiom of RC might remit the DM-induced renal damage through the AGE-RAGE signaling pathway to improve metabolic parameters and protect renal structure and function.

Multiple Biological Effects of an Iridoid Glucoside, Catalpol and Its Underlying Molecular Mechanisms

Catalpol, an iridoid glucoside, is widely distributed in many plant families and is primarily obtained from the root of Rehmanniaglutinosa Libosch. Rehmanniaglutinosa is a plant very commonly used in Chinese and Korean traditional medicine for various disorders, including diabetes mellitus, neuronal disorders, and inflammation. Catalpol has been studied extensively for its biological properties both in vitro and in vivo. This review aims to appraise the biological effects of catalpol and their underlying mechanisms. An extensive literature search was conducted using the keyword "Catalpol" in the public domains of Google scholar, PubMed, and Scifinder. Catalpol exhibits anti-diabetic, cardiovascular protective, neuroprotective, anticancer, hepatoprotective, anti-inflammatory, and anti-oxidant effects in experimental studies. Anti-inflammatory and antioxidant properties are mostly related for its biological effect. However, some specific mechanisms are also elucidated. Elevated serotonin and BDNF level by catalpol significantly protect against depression and neurodegeneration. Catalpol demonstrated an increased mitochondrial biogenesis and activation of PI3K/Akt pathway for insulin sensitizing effect. Further, its cardiovascular protective effect was linked to PI3K/Akt, apelin/APJ and Jak-Stat pathway. Catalpol produced a significant reduction in cell proliferation and an increase in apoptosis in different cancer conditions. Overall, catalpol demonstrated multiple biological effects due to its numerous mechanisms including anti-inflammatory and antioxidant effects.

RhoA/ROCK-2 Pathway Inhibition and Tight Junction Protein Upregulation by Catalpol Suppresses Lipopolysaccaride-Induced Disruption of Blood-Brain Barrier Permeability

Lipopolysaccaride (LPS) directly or indirectly injures brain microvascular endothelial cells (BMECs) and damages the intercellular tight junction that gives rise to altered blood-brain barrier (BBB) permeability. Catalpol plays a protective role in LPS-induced injury, but whether catalpol protects against LPS-caused damage of BBB permeability and the underlying mechanism remain to be delineated. Prophylactic protection with catalpol (5 mg/kg, i.v.) consecutively for three days reversed the LPS-induced damage of BBB by decreased Evans Blue (EB) leakage and restored tight junctions in C57 mice. Besides, catalpol co-administrated with LPS increased BMECs survival, decreased their endothelin-1, TNF-Α and IL-6 secretion, improved transmembrane electrical resistance in a time-dependent manner, and in addition increased the fluorescein sodium permeability coefficient of BMECs. Also, transmission electron microscopy showed catalpol protective effects on tight junctions. Fluorescence staining displayed that catalpol reversed the rearrangement of the cytoskeleton protein F-actin and upregulated the tight junction protein of claudin-5 and ZO-1, which have been further demonstrated by the mRNA and protein expression levels of ZO-1, ZO-2, ZO-3, claudin-5, and occludin. Moreover, catalpol concurrently downregulated the mRNA and protein levels of RhoA, and ROCK2, the critical proteins in the RhoA/ROCK2 signaling pathway. This study thus indicated that catalpol, via inhibition of the RhoA/ROCK2 signaling pathway, reverses the disaggregation of cytoskeleton actin in BMECs and prevents down-regulation of junctional proteins, such as claudin-5, occludin, and ZO-1, and decreases endothelin-1 and inflammatory cytokine secretion, eventually alleviating the increase in LPS-induced BBB permeability.