Preventive effect of tetramethylpyrazine on intestinal mucosal injury in rats with acute necrotizing pancreatitis

Network pharmacology-based investigation and experimental validation of the therapeutic potential and molecular mechanism of Danshen Chuanxiongqin injection in acute pancreatitis

BACKGROUND

Danshen Chuanxiong Injection (DCI) has demonstrated significant clinical efficacy in the treatment of acute pancreatitis (AP); however, the precise molecular mechanisms underlying its therapeutic effects remain incompletely understood.

OBJECTIVE

In this study, we employed network pharmacology analysis to comprehensively investigate the active components, potential targets, and signaling pathways involved in DCI-mediated treatment of AP.

METHODS

We utilized the mouse pancreatic acinar cell line 266-6 to establish an cholecystokinin (CCK)-induced AP cell injury model and evaluated cell viability using the Cell counting kit-8 assay. Western blotting and quantitative PCR were employed to determine the expression levels of key target proteins and genes.

RESULTS

Network pharmacology analysis identified a total of 144 active components and 430 potential targets within DCI. By integrating data from public databases, we identified 762 AP-related genes. Among these, we identified 93 potential targets that may be involved in the therapeutic effects of DCI for AP. These targets were significantly enriched in biological processes such as oxidative stress, regulation of cytokine production, leukocyte migration, and the TNF signaling pathway. Molecular docking studies revealed a high binding affinity between the active components and the key targets AKT1 and NFKBA, indicative of potential interaction. Additionally, CCK-induced acinar cell injury led to upregulation of AKT1, NFKBA, and P53 proteins, as well as TNF, IL6, and MMP9 genes. Conversely, treatment with DCI dose-dependently attenuated CCK-induced acinar cell injury and restored the expression levels of the aforementioned proteins and genes.

CONCLUSION

Overall, this study provides a comprehensive understanding of the molecular mechanisms underlying the therapeutic effects of DCI in the treatment of AP. Our findings confirm the protective effect of DCI against CCK-induced acinar cell injury and its regulation of key targets.

Tetramethylpyrazine: A review on its mechanisms and functions

Ligusticum chuanxiong Hort (known as Chuanxiong in China, CX) is one of the most widely used and long-standing medicinal herbs in China. Tetramethylpyrazine (TMP) is an alkaloid and one of the active components of CX. Over the past few decades, TMP has been proven to possess several pharmacological properties. It has been used to treat a variety of diseases with excellent therapeutic effects. Here, the pharmacological characteristics and molecular mechanism of TMP in recent years are reviewed, with an emphasis on the signal-regulation mechanism of TMP. This review shows that TMP has many physiological functions, including anti-oxidant, anti-inflammatory, and anti-apoptosis properties; autophagy regulation; vasodilation; angiogenesis regulation; mitochondrial damage suppression; endothelial protection; reduction of proliferation and migration of vascular smooth muscle cells; and neuroprotection. At present, TMP is used in treating cardiovascular, nervous, and digestive system conditions, cancer, and other conditions and has achieved good curative effects. The therapeutic mechanism of TMP involves multiple targets, multiple pathways, and bidirectional regulation. TMP is, thus, a promising drug with great research potential.

Tetramethylpyrazine (TMP) protects rats against acute pancreatitis through NF-κB pathway

Acute pancreatitis (AP) is a digestive disease characterized by pancreatic inflammation. Tetramethylpyrazine (TMP) has been effectively used to ameliorate the damage on intestinal mucosa injury in rats with acute necrotizing pancreatitis (ANP). We aim to study the protective effect of TMP on caerulein-induced AP and to explore the possible mechanism. The mice randomized into control and different experimental groups. AP was induced in mice by 6-hourly intraperitoneal (i.p) injections of caerulein (50 μg/kg at 1 h interval). TMP (i.p, 10 mg/kg, 1 h interval) was administered 3 h before caerulein injection. Administration of TMP attenuated the severity of AP as shown by the histopathology, reduced serum amylase activity and pro-inflammatory cytokines TNF-α and IL-6. Further, TMP enhances the beneficial effect by reducing caerulein-induced NF-κB activation and inducing cell apoptosis in pancreas. Therefore, inhibition of nuclear factor-kappa B(NF-κB) signals by TMP represents a potential therapeutic strategy for the treatment of acute pancreatitis.

Intravenous administration of tetramethylpyrazine reduces intestinal ischemia-reperfusion injury in rats

Intestinal ischemia-reperfusion injury (IIRI) is a life-threatening condition requiring prompt medical intervention. Tetramethylpyrazine (TMP) is a biologically active alkaloid isolated from Ligusticum wallichii. Previously, it was shown that TMP causes vasodilatation and inhibition of platelet aggregation as well as exhibits significant antioxidant effects. Therefore, the aim of the present study was to evaluate possible therapeutic effects of TMP in the prevention of IIRI. Wistar rats (n = 80) were randomly divided into eight experimental groups and subjected to a 1 h occlusion of cranial mesenteric artery followed by 0, 1, 12, and 24 h period of reperfusion. Thirty minutes before the IIRI animals received either TMP (30 mg/kg, i.v.) or identical volume of saline. In addition, a control group of 10 animals was not exposed to IIRI. Intestine morphology was evaluated by using histopathological injury index examination (HII), goblet and Paneth cells quantification as well as by applying immunofluorescent methods such as InSitu TUNEL and caspase-3 positivity assessment. Here we showed that preconditioning with TMP prior IIRI decreases the grade of injury. Significant reduction of HII was detected in TMP pretreated groups after 0, 1, and 12 h of reperfusion where injury reduction up to 75% was found. Lower histopathological damage in preconditioned groups was accompanied with increased number of secretory epithelial cells and decreased number of apoptotic cells. These results demonstrate the protective effect of TMP on the small intestine mucosa, suggesting administration of TMP as a molecule for pharmacological intervention against IIRI.

TREM-1 Promotes Pancreatitis-Associated Intestinal Barrier Dysfunction

Severe acute pancreatitis (SAP) can cause intestinal barrier dysfunction (IBD), which significantly increases the disease severity and risk of mortality. We hypothesized that the innate immunity- and inflammatory-related protein-triggering receptor expressed on myeloid cells-1 (TREM-1) contributes to this complication of SAP. Thus, we investigated the effect of TREM-1 pathway modulation on a rat model of pancreatitis-associated IBD. In this study we sought to clarify the role of TREM-1 in the pathophysiology of intestinal barrier dysfunction in SAP. Specifically, we evaluated levels of serum TREM-1 and membrane-bound TREM-1 in the intestine and pancreas from an animal model of experimentally induced SAP. TREM-1 pathway blockade by LP17 treatment may suppress pancreatitis-associated IBD and ameliorate the damage to the intestinal mucosa barrier.

Protective effects of Ligustrazine, Kakonein and Panax Notoginsenoside on the small intestine and immune organs of rats with severe acute pancreatitis

BACKGROUND

Severe acute pancreatitis (SAP) is characterized by fatal pathogenic conditions and a high mortality. It is important to study SAP complicated with multiple organ injury. In this study we compared the protective effects of three traditional Chinese medicines (Ligustrazine, Kakonein and Panax Notoginsenoside) on the small intestine and immune organs (thymus, spleen and lymph nodes) of rats with SAP and explored their mechanism of action.

METHODS

One hundred forty-four rats with SAP were randomly divided into model control, Ligustrazine-treated, Kakonein-treated, and Panax Notoginsenoside-treated groups (n=36 per group). Another 36 normal rats comprised the sham-operated group. According to the different time points after operation, the experimental rats in each group were subdivided into 3-, 6- and 12-hour subgroups (n=12). At various time points after operation, the mortality rate of rats and pathological changes in the small intestine and immune organs were recorded and the serum amylase levels were measured.

RESULTS

Compared to the model control groups, the mortality rates in all treated groups declined and the pathological changes in the small intestine and immune tissues were relieved to different degrees. The serum amylase levels in the three treated groups were significantly lower than those in the model control group at 12 hours. The pathological severity scores for the small intestinal mucosa, thymus and spleen (at 3 and 12 hours) in the Ligustrazine-treated group, for the thymus (at 3 and 12 hours) and spleen (at 3 and 6 hours) in the Kakonein-treated group, and for the thymus (at 3 hours) and spleen (at 3 hours) in the Panax Notoginsenoside-treated group were significantly lower than those in the model control group. The pathological severity scores of the small intestinal mucosa (at 6 and 12 hours) and thymus (at 6 hours) in the Ligustrazine-treated group were significantly lower than those in the Kakonein- and Panax Notoginsenoside-treated groups.

CONCLUSIONS

All the three traditional Chinese drugs significantly alleviated the pathological changes in the small intestine and immune organs of SAP rats. Ligustrazine was the most effective one among them.

Protective effect of clodronate-containing liposomes on intestinal mucosal injury in rats with severe acute pancreatitis

BACKGROUND

Severe acute pancreatitis (SAP) can result in intestinal mucosal injury. This study aimed to demonstrate the protective effect of clodronate-containing liposomes on intestinal mucosal injury in rats with SAP.

METHODS

Liposomes containing clodronate or phosphate buffered saline (PBS) were prepared by the thin-film method. SAP models were prepared by a uniform injection of sodium taurocholate (2 mL/kg body weight) into the subcapsular space of the pancreas. Sprague-Dawley rats were randomly divided into a control group (C group), a SAP plus PBS-containing liposomes group (P group) and a SAP plus clodronate-containing liposomes group (T group). At 2 and 6 hours after the establishment of SAP models, 2 mL blood samples were taken from the superior mesenteric vein to measure the contents of serum TNF-alpha and IL-12. Pathological changes in the intestine and pancreas were observed using hematoxylin and eosin staining, while apoptosis was detected using TUNEL staining. In addition, the macrophage markers cluster of differentiation 68 (CD68) in the intestinal tissue was assessed with immunohistochemistry.

RESULTS

At the two time points, the levels of TNF-alpha and IL-12 in the P group were higher than those in the C group (P<0.05). Compared with the P group, the levels of TNF-alpha and IL-12 decreased in the T group (P<0.05). The pathological scores of the intestinal mucosa and pancreas in the T group were lower than those of the P group. In the T group, large numbers of TUNEL-positive cells were observed, but none or few in the C and P groups. The number of CD68-positive macrophages decreased in the T group.

CONCLUSIONS

Clodronate-containing liposomes have protective effects against intestinal mucosal injury in rats with SAP. The blockade of macrophages may provide a novel therapeutic strategy in SAP.

Attenuating effect of pretreatment with Yiqifumai on lipopolysaccharide-induced intestine injury and survival rate in rat

Background

Yiqifumai is a traditional Chinese medicine compound preparation used for treatment of microcirculatory disturbance-related diseases in China. We have previous reported that pretreatment with Yiqifumai could improve the lipopolysaccharide (LPS) -induced microcirculatory disturbance in rat mesentery. The present study intended to investigate the effect of pretreatment with Yiqifumai on intestine injury and survival rate of the rats subjected to LPS challenge.

Methods

Male Wistar rats were continuously infused with LPS (5 mg kg^-1 body weight h^-1) via the left jugular vein for 90 min. In some rats, Yiqifumai 80 (mg/kg) was administrated through the left jugular vein 10 min before LPS infusion. The mean arterial pressure (MAP), heart rate (HR), rectal temperature (RT), respiratory rate (RR) and survival rate were measured at 24 h, 48 h and 72 h after LPS infusion. At 72 h after exposure to LPS, the intestine morphology was observed under a stereomicroscope and the immunohistochemistry staining of intestine was conducted to evaluate the expression of intercellular adhesion molecule 1 (ICAM-1) and the number of myeloperoxidase (MPO) positive cells in tissue. After observation of intestine microcirculation, blood was collected from the abdominal aorta of each animal to analyze the level of inflammatory markers in plasma, including TNF-α and MCP-1.

Results

Compared to the control, LPS infusion significantly decreased MAP and the survival rate and increased the HR, RT and RR, as well as elicited leukocyte infiltration, intestine hemorrhage, enhanced expression of ICAM-1 and raised level of inflammatory markers. All of indicators, except for the RT, were significantly attenuated by Yiqifumai, in contrast to the LPS group.

Conclusions

The results demonstrated the potential of pretreatment with Yiqifumai to ameliorate rat intestine injury, inflammatory response to LPS and the decrease in survival rate caused by LPS challenge.

Clodronate-containing liposomes attenuate lung injury in rats with severe acute pancreatitis

OBJECTIVES

Severe acute pancreatitis (SAP) can lead to acute lung injury (ALI). The purpose of this paper is to investigate the protective effect of clodronate-containing liposomes on ALI in rats with SAP.

METHODS

The thin film method was used to prepare liposomes. Sprague-Dawley rats were randomly divided into three groups. After the SAP model was established by injecting 5% (w/v) sodium taurocholate (2 ml/kg body weight) into the subcapsular space of the pancreata, normal saline was administered to the control (C) group, phosphate buffer solution (PBS)-containing liposome to the P group, and clodronate-containing liposome to the T group through tail veins. Blood samples were obtained from the superior mesenteric vein at 2 and 6 h to measure the levels of amylase, interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α). Morphological changes in the pancreata and lung were observed using hematoxylin and eosin (H&E) staining, while cell apoptosis was detected using terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL). In addition, the macrophage marker cluster of differentiation 68 (CD68) in lung tissue was detected with immunohistochemistry.

RESULTS

Blood levels of amylase, IL-6, and TNF-α were significantly increased in the P group compared to those in the T group (P<0.05). In the T group, large numbers of TUNEL-positive cells were observed, but no or few in the C and P groups. Gross inspection and H&E staining of pancreata and lung showed dramatic tissue damage, including inflammation and necrosis in the P group. Less remarkable changes were noted in the T group, and the C group exhibited normal histology. The histological scores according to Kaiser's criteria were consistent with H&E findings. The number of CD68-positive macrophages decreased in the T group.

CONCLUSIONS

Clodronate-containing liposomes have a protective effect against ALI in rats with SAP. Blockade of macrophages may represent a novel therapeutic strategy in SAP.

Dynamic changes in the levels of serum interleukin-2 and interleukin-10 and the expression of Fas in the intestinal mucosa of rats with severe acute pancreatitis

AIM: To investigate the dynamic changes in the levels of serum interleukin (IL)-2 and IL-10 sFas and IL-2/IL-10 in rats with severe acute pancreatitis (SAP), and to explore the expression of Fas in the intestinal mucosa of rats with severe acute pancreatitis.

METHODS: A total of 64 Sprague-Dawley (SD) rats were randomly divided into normal control group and SAP group. A SAP model was induced by injection of 50 g/L sodium taurocholate under the pancreatic membrane. The normal control group received isovolumetric injection of 9 g/L physiological saline solution using the same method. Blood samples from the rats in each group were obtained via the superior mesenteric vein to measure the levels of IL-2, IL-10 and sFas, and to calculate the value of IL-2/IL-10. The levels of IL-2, IL-10 and sFas were determined by ELISA. The severity of pancreas and intestinal mucosal injury was evaluated by pathologic score. The expression of Fas in intestinal mucosal tissue was determined by immunohistochemistry.

RESULTS: The levels of serum IL-2 in the SAP group were significantly higher than those in the normal control group at 0.5 h after injury (3.53 ± 0.62 ng/L vs 2.79 ± 0.51 ng/L, 4.35 ± 1.11 ng/L vs 2.93 ± 0.89 ng/L, 6.94 ± 1.55 ng/L vs 4.81 ± 1.23 ng/L, 4.80 ± 1.10 ng/L vs 3.41 ± 0.72 ng/L, P < 0.01) and peaked at 6 h after injury. The levels of serum IL-10 in the SAP group were significantly higher than those in the normal control group at 6 h after injury (494.98 ± 11.23 ng/L vs 89.18 ± 32.52 ng/L, 93.28 ± 25.81 ng/L vs 77.15 ± 22.60 ng/L, P < 0.01). The IL-2/IL-10 ratio in the SAP group was significantly higher than that in the normal control group at 0.5 h and 2 h after injury, and significantly lower than that in the normal control group at 6 h after injury (P < 0.01), after which this ratio returned to the control level (P > 0.05). The pathological changes were significantly aggravated in the SAP group compared with the normal group. Immunohistochemistry staining showed. Fas from normal intestinal tissue. Fas expression in intestinal tissue gradually increased 0.5 h after the induction of pancreatitis, and its a peak at 12 h after induction.

CONCLUSION: Fas is involved in the pathogenesis of pancreatitis-associated intestinal injury. The mechanisms underlying this involvement of Fas may be related to Fas-mediated T helper cell apoptosis.