OBJECTIVE: To observe the effect of electroacupuncture (EA) at "Neiguan" (PC 6) on myocardial fibrosis in spontaneously hypertensive rats (SHR), and explore preliminarily the mediating role of cholinergic anti-inflammatory pathway (CAP) and its downstream nuclear factor κB (NF-κB) signaling pathway. METHODS: Six 12-week-old WKY male rats were employed as the normal group. Eighteen 12-week-old SHR were randomly divided into 3 groups, i.e. a model group, an EA group and a blocking group (EA after blocking α7 nicotinic acetylcholine receptor [α7nAchR]), with 6 rats in each one. In the EA group, EA was delivered at "Neiguan"(PC 6) and the site 0.5 cm from its left side, with disperse-dense wave, 2 Hz/15 Hz in frequency and 1 mA in current intensity. One intervention took 30 min and was given once every 2 days, lasting 8 weeks. In the blocking group, prior to each EA, the α7nAchR specific blocker, α-bungartoxin was injected intravenously in the tails of the rats. After EA intervention, the systolic blood pressure (SBP), the diastolic blood pressure (DBP) and the mean arterial pressure (MAP) were measured with non-invasive blood pressure monitor. Using echocardiogram, the left ventricular (LV) anterior wall end-diastolic thickness (LVAWd) , LV posterior wall end-diastolic thickness (LVPWd) and the LV end-diastolic internal diameter (LVIDd) were measured. The level of hydroxyproline (Hyp) in the myocardial tissue was determined by using alkaline hydrolysis, and that of acetylcholine (Ach) was detected by ELISA. With the real-time PCR adopted, the mRNA expression of NF-κB p65, tumor necrosis factor α (TNF-α), interleukin (IL)-1β and IL-6 were determined. RESULTS: Compared with the normal group, SBP, DBP, MAP, LVAWd and LVPWd were increased (P<0.01), and LVIDd was decreased (P<0.01) in the rats of the model group. SBP, DBP, MAP and LVAWd were dropped (P<0.01, P<0.05), and LVIDd rose (P<0.01) in the EA group when compared with those in the model group. The differences in the above indexes were not statistically significant between the blocking group and the model group (P>0.05). Compared with the normal group, Hyp level and the mRNA expression of NF-κB p65, TNF-α, IL-1β and IL-6 in the myocardial tissue increased (P<0.01, P<0.05) and Ach level decreased (P<0.01) in the model group. Hyp level, the mRNA expression of NF-κB p65, TNF-α, IL-1β and IL-6 in the myocardial tissue were reduced (P<0.05, P<0.01) and Ach level rose (P<0.01) in the EA group when compared with those in the model group. These indexes were not different statistically between the blocking group and the model group (P>0.05). CONCLUSION CAP may be involved in ameliorating the pathological damage of myocardial fibrosis during EA at "Neiguan"(PC 6). The underlying effect mechanism is associated with up-regulating the neurotransmitter, Ach and down-regulating mRNA expression of NF-κB p65 and pro-inflammatory factors such as TNF-α, IL-1β and IL-6 in myocardial tissue.
Rats ; Male ; Animals ; Rats, Inbred SHR ; NF-kappa B/metabolism* ; Rats, Inbred WKY ; Electroacupuncture ; Tumor Necrosis Factor-alpha/metabolism* ; Interleukin-6/metabolism* ; Neuroimmunomodulation ; alpha7 Nicotinic Acetylcholine Receptor ; Acetylcholine ; Fibrosis ; RNA, Messenger

It is well established that increased excitability of the presympathetic neurons in the hypothalamic paraventricular nucleus (PVN) during hypertension leads to heightened sympathetic outflow and hypertension. However, the mechanism underlying the overactivation of PVN presympathetic neurons remains unclear. This study aimed to investigate the role of endogenous corticotropin-releasing factor (CRF) on the excitability of presympathetic neurons in PVN using Western blot, arterial blood pressure (ABP) and renal sympathetic nerve activity (RSNA) recording, CRISPR/Cas9 technique and patch-clamp technique. The results showed that CRF protein expression in PVN was significantly upregulated in spontaneously hypertensive rats (SHRs) compared with normotensive Wistar-Kyoto (WKY) rats. Besides, PVN administration of exogenous CRF significantly increased RSNA, heart rate and ABP in WKY rats. In contrast, knockdown of upregulated CRF in PVN of SHRs inhibited CRF expression, led to membrane potential hyperpolarization, and decreased the frequency of current-evoked firings of PVN presympathetic neurons, which were reversed by incubation of exogenous CRF. Perfusion of rat brain slices with artificial cerebrospinal fluid containing CRF receptor 1 (CRFR1) blocker, NBI-35965, or CRF receptor 2 (CRFR2) blocker, Antisauvagine-30, showed that blocking CRFR1, but not CRFR2, hyperpolarized the membrane potential and inhibited the current-evoked firing of PVN presympathetic neurons in SHRs. However, blocking CRFR1 or CRFR2 did not affect the membrane potential and current-evoked firing of presympathetic neurons in WKY rats. Overall, these findings indicate that increased endogenous CRF release from PVN CRF neurons enhances the excitability of presympathetic neurons via activation of CRFR1 in SHRs.
Rats ; Animals ; Rats, Inbred SHR ; Paraventricular Hypothalamic Nucleus/physiology* ; Receptors, Corticotropin-Releasing Hormone/metabolism* ; Rats, Inbred WKY ; Corticotropin-Releasing Hormone/metabolism* ; Neurons/physiology* ; Hypertension ; Sympathetic Nervous System

This study investigated the drug delivery performance of oral co-loaded puerarin(PUE) and daidzein(DAZ) mixed micelles(PUE/DAZ-FS/PMMs) from the perspectives of pharmacokinetics, pharmacodynamics, and tissue distribution. The changes in PUE plasma concentration in rats were evaluated based on PUE suspension, single drug-loaded micelles(PUE-FS/PMMs), and co-loaded micelles(PUE/DAZ-FS/PMMs). Spontaneously hypertensive rats(SHR) were used to monitor systolic blood pressure, diastolic blood pressure, and mean arterial pressure for 10 weeks after administration by tail volume manometry. The content of PUE in the heart, liver, spleen, lung, kidney, brain, and testes was determined using LC-MS/MS. The results showed that compared with PUE suspension and PUE-FS/PMMs, PUE/DAZ-FS/PMMs significantly increased C_(max) in rats(P<0.01) and had a relative bioavailability of 122%. The C_(max), AUC_(0-t), AUC_(0-∞), t_(1/2), and MRT of PUE/DAZ-FS/PMMs were 1.77, 1.22, 1.22, 1.17, and 1.13 times higher than those of PUE suspension, and 1.76, 1.16, 1.08, 0.84, and 0.78 times higher than those of PUE-FS/PMMs, respectively. Compared with the model control group, PUE/DAZ-FS/PMMs significantly reduced systolic blood pressure, diastolic blood pressure, and mean arterial pressure in SHR rats(P<0.05). The antihypertensive effect of PUE/DAZ-FS/PMMs was greater than that of PUE suspension, and even greater than that of PUE-FS/PMMs at high doses. Additionally, the distribution of PMMs in various tissues showed dose dependency. The distribution of PMMs in the kidney and liver, which are metabolically related tissues, was lower than that in the suspension group, while the distribution in the brain was higher than that in the conventional dose group. In conclusion, PUE/DAZ-FS/PMMs not only improved the bioavailability of PUE and synergistically enhanced its therapeutic effect but also prolonged the elimination of the drug to some extent. Furthermore, the micelles facilitated drug penetration through the blood-brain barrier. This study provides a foundation for the development of co-loaded mixed micelles containing homologous components.
Rats ; Animals ; Micelles ; Tissue Distribution ; Chromatography, Liquid ; Tandem Mass Spectrometry ; Rats, Inbred SHR ; Isoflavones/pharmacology*

This study aims to investigate the effects of Blaps rynchopetera Fairmaire and/or cyclophosphamide on the proliferation and apoptosis of lung cancer cells and decipher the underlying mechanism. B. rynchopetera and cyclophosphamide-containing serum and blank serum were prepared from SD rats. Cell counting kit-8(CCK-8) assay was employed to examine the proliferation of lung cancer cell lines A549 and Lewis treated with corresponding agents. The Jin's formula method was used to evaluate the combined effect of the two drugs. According to the evaluation results, appropriate drug concentrations and lung cancer cell line were selected for subsequent experiments, which included control, B. rynchopetera, cyclophosphamide, B. rynchopetera + cyclophosphamide, and B. rynchopetera + Wnt/β-catenin pathway agonist lithium chloride(LiCl) groups. Immunocytochemistry was employed to measure the expression of proliferation-related proteins in Lewis cells after drug interventions. Flow cytometry was employed to determine the cell cycle and apoptosis. The expression levels of proliferating cell nuclear antigen(PCNA), cyclinD1, B-cell lymphoma 2(Bcl-2), Bcl-2-assiocated X protein(Bax), Wnt1, and β-catenin were determined by Western blot. The results showed that B. rynchopetera and/or cyclophosphamide significantly inhibited the proliferation of A549 and Lewis cells. Compared with B. rynchopetera alone, the combination increased the inhibition rate on cell proliferation. The combination of B. rynchopetera and cyclophosphamide demonstrated a synergistic effect according to Jin's formula-based evaluation. Compared with the control group, the B. rynchopetera, cyclophosphamide, and B. rynchopetera + cyclophosphamide groups showed increased proportion of Lewis cells in G_0/G_1 phase, increased apoptosis rate, up-regulated expression of Bax, and down-regulated expression of PCNA, cyclinD1, Bcl-2, Wnt1, and β-catenin. Compared with the cyclophosphamide group, the combination group showed increased proportion of cells in G_0/G_1 phase, increased apoptosis rate, up-regulated expression of Bax, and down-regulated expression of PCNA, cyclinD1, Bcl-2, Wnt1, and β-catenin. Compared with the B. rynchopetera group, the B. rynchopetera + LiCl group had deceased proportion of cells in G_0/G_1 phase, decreased apoptosis rate, down-regulated expression of Bax, and up-regulated expression of PCNA, cyclinD1, Bcl-2, Wnt1, and β-catenin. The results indicated that B. rynchopetera could inhibit the proliferation, arrest the cell cycle, and induce the apoptosis of lung cancer cells by inhibiting the Wnt/β-catenin signaling pathway. Moreover, B. rynchopetera had a synergistic effect with cyclophosphamide.
Rats ; Animals ; Wnt Signaling Pathway ; Lung Neoplasms/genetics* ; beta Catenin/metabolism* ; Proliferating Cell Nuclear Antigen ; bcl-2-Associated X Protein/metabolism* ; Rats, Inbred Lew ; Rats, Sprague-Dawley ; Apoptosis ; Proto-Oncogene Proteins c-bcl-2/metabolism* ; Cell Proliferation ; Cyclophosphamide ; Cell Line, Tumor

OBJECTIVE: To study effects of Shenmai Injection on hypertensive heart failure and its mechanism for inhibiting myocardial fibrosis. METHODS: Salt-sensitive (Dahl/SS) rats were fed with normal diet (0.3% NaCl) and the high-salt diet (8% NaCl) to observe the changes in blood pressure and heart function, as the control group and the model group. Salt-insensitive rats (SS-13BN) were fed with the high-salt diet (8% NaCl) as the negative control group. After modeling, the model rats were randomly divided into heart failure (HF) group, Shenmai Injection (SMI) group and pirfenidone (PFD) group by a random number table, with 6 rats in each group. They were given sterilized water, SMI and pirfenidone, respectively. Blood pressure, cardiac function, fibrosis and related molecular expression were detected by sphygmomanometer, echocardiogram, enzyme linked immunosorbent assay (ELISA), hematoxylin-eosin staining, Masson staining, immunofluorescence and qPCR analysis. RESULTS: After high-salt feeding, compared with the control and negative control group, in the model group the blood pressure increased significantly, the left ventricular ejection fraction (LVEF) and left ventricular fraction shortening (LVFS) were significantly reduced, and the serum NT-proBNP concentration increased significantly (all P<0.05); furthermore, the arrangement of myocardial cells was disordered, the edema was severe, and the degree of myocardial fibrosis was also significantly increased (P<0.05); the protein and mRNA expressions of collagen type I (Col I) were up-regulated (P<0.05), and the mRNA expressions of transforming growth factor β 1 (TGF- β 1), Smad2 and Smad3 were significantly up-regulated (P<0.05). Compared with HF group, after intervention of Shenmai Injection, LVEF and LVFS increased, myocardial morphology was improved, collagen volume fraction decreased significantly (P<0.05), and the mRNA expressions of Col I, TGF- β 1, Smad2 and Smad3, as well as Col I protein expression, were all significantly down-regulated (all P<0.05). CONCLUSION Myocardial fibrosis is the main pathological manifestation of hypertensive heart failure, and Shenmai Injection could inhibit myocardial fibrosis and effectively improve heart failure by regulating TGF-β 1/Smad signaling pathway.
Rats ; Animals ; Stroke Volume ; Sodium Chloride ; Rats, Inbred Dahl ; Ventricular Function, Left ; Heart Failure ; Transforming Growth Factor beta1/metabolism* ; Hypertension ; Fibrosis ; RNA, Messenger

OBJECTIVE: To investigate the effect of electroacupuncture (EA) at Neiguan (PC 6) on myocardial fibrosis in spontaneously hypertensive rats (SHRs), and to explore the contribution of interleukin-1 β (IL-1 β), insulin-like growth factor 1 (IGF-1), and transforming growth factor β 1 (TGF- β 1) to the effects. METHODS: Nine 12-weeks-old Wistar Kyoto (WKY) male rats were employed as the normal group. Twenty-seven SHRs were equally randomized into SHR, SHR+EA, and SHR + sham groups. EA was applied at bilateral PC 6 once a day 30 min per day in 8 consecutive weeks. After 8-weeks EA treatment at PC 6, histopathologic changes of collagen type I (Col I), collagen type 1 (Col 1) and the levels of IGF-1, 1L-1 β, TGF- β 1, matrix metalloproteinase (MMP)-2 and MMP-9 were examined in myocardial tissure respectively. RESULTS: After 8-weeks EA treatment at PC 6, the enhanced myocardial fibrosis in SHRs were characterized by the increased mean fluorescence intensity of Col I and Col 1 in myocardium tissue (P<0.01). All these abnormal alterations above in SHR + EA group was significantly lower compared with the SHR group (P<0.01). Meanwhile, the increased levels of IL-1 β, IGF-1, TGF-β 1 in serum or myocardial tissue of SHRs, diminished MMP 9 mRNA expression in SHRs were also markedly inhibited after 8 weeks of EA treatment (P<0.05 or P<0.01). Furthermore, the contents of IL-1 β, IGF-1, TGF-β 1 in myocardial tissue were positively correlated with the systolic blood pressure and hydroxyproline respectively (P<0.01). CONCLUSION EA at bilateral PC 6 could ameliorate cardiac fibrosis in SHRs, which might be mediated by regulation of 1L-1 β/IGF-1-TGF- β 1-MMP9 pathway.
Rats ; Animals ; Male ; Rats, Inbred WKY ; Electroacupuncture ; Hypertension/therapy* ; Insulin-Like Growth Factor I ; Interleukin-1beta ; Rats, Inbred SHR ; Essential Hypertension ; Myocardium/pathology* ; Collagen Type I ; Fibrosis

OBJECTIVE: To investigate the effects of different manners of heat exposure on thoracic aorta injury in spontaneously hypertensive rats (SHRs) and explore the underlying mechanism. METHODS: Normal 6 to 7-week-old male SHRs were randomized into control group (cage at room temperature), intermittent heat exposure group (SHR-8 group, exposed to 32 ℃ for 8 h daily for 7 days) and SHR-24 group (with continuous exposure to 32 ℃ for 7 days). After the treatments, the pathologies of the thoracic aorta of the rats were observed with HE staining, and the expressions of Beclin1, LC3B and p62 were detected with Western blotting and immunofluorescence assay; TUNEL staining was used to observe cell apoptosis in the thoracic aorta, and the expressions of caspase-3, Bax, and Bcl-2 were detected using Western blotting. The effects of intraperitoneal injections of 3-MA (an autophagy agonist), rapamycin (an autophagy inhibitor) or compound C 30 min before intermittent heat exposure on the expressions of proteins associated with autophagy, apoptosis and the AMPK/mTOR/ULK1 pathway in the aorta were examined with immunohistochemistry. RESULTS: In SHR-8 group, the rats showed incomplete aortic intima with disordered cell distribution and significantly increased expressions of Beclin1, LC3II/LC3I and Bax, lowered expressions of p62 and Bcl-2, and increased apoptotic cells in the thoracic aorta (P < 0.05). Pretreatment with 3-MA obviously inhibited the expressions of autophagy- and apoptosis-related proteins, whereas rapamycin promoted their expressions. Compared with the control group, the rats in SHR-8 group had significantly down-regulated p-mTOR and up-regulated p-AMPK and p-ULK1 expression of in the aorta; Treatment with compound C obviously lowered the expressions of p-AMPK and p-ULK1 and those of LC3B and Beclin1 as well. CONCLUSION In SHRs, intermittent heat exposure causes significant pathologies and promotes autophagy and apoptosis in the thoracic aorta possibly by activating the AMPK/mTOR/ULK1 pathway.
Rats ; Male ; Animals ; Rats, Inbred SHR ; AMP-Activated Protein Kinases/metabolism* ; bcl-2-Associated X Protein/metabolism* ; Aorta, Thoracic ; Beclin-1 ; Hot Temperature ; TOR Serine-Threonine Kinases/metabolism* ; Proto-Oncogene Proteins c-bcl-2/metabolism* ; Apoptosis ; Aortic Diseases ; Autophagy ; Autophagy-Related Protein-1 Homolog/metabolism*

OBJECTIVE: To investigate the correlation of inducible co-stimulatory molecules (ICOS) with mesenteric vascular endothelial- mesenchymal transition (EndMT) and sclerosis in spontaneously hypertensive rats (SHR). METHODS: Twenty 4-week-old WKY rats and 20 SHRs of the same strain were both randomly divided into 4 groups for observation at 4, 6, 10 and 30 weeks of age. ICOS expression frequency in rat spleen CD4⁺T cells was analyzed using flow cytometry, and the expressions of ICOS, VE-cad, α-SMA and Col3 mRNA in rat mesentery were detected by RT-PCR. The distributions of ICOS, IL-17A and TGF-β in rat mesentery were detected by immunohistochemistry. The levels of IL-17A and TGF-β in rat plasma were measured using ELISA. The morphological changes of rat mesenteric vessels were observed with Masson staining. Spearman or Pearson correlation analyses were used to evaluate the correlation between ICOS expression and the expressions of the markers of vascular EndMT and sclerosis. RESULTS: Compared with the control WKY rats, the SHRs began to show significantly increased systolic blood pressure and ICOS expression frequency on CD4⁺T cells at 6 weeks of age (P < 0.05). In the SHRs, the mRNA and protein expressions of ICOS, α-SMA, Col3, IL-17A and TGF-β in the mesentery were significantly higher than those in control group (P < 0.05), while the mRNA and protein expressions of VE-cad started to reduce significantly at 10 weeks of age (P < 0.05). The plasma levels of IL-17A and TGF-β were significantly increased in SHRs since 6 weeks of age (P < 0.05) with progressive worsening of mesenteric vascular sclerosis (P < 0.05). ICOS mRNA and protein expression levels in the mesenteric tissues of SHRs began to show positive correlations with α-SMA and Col3 expression levels and the severity of vascular sclerosis at 6 weeks of age (P < 0.05) and a negative correlation with VE-cad expression level at 10 weeks (P < 0.05). CONCLUSION ICOS play an important pathogenic role in EndMT and sclerosis of mesenteric vessels in essential hypertension by mediating related immune responses.
Rats ; Animals ; Rats, Inbred SHR ; Rats, Inbred WKY ; Hypertension ; Interleukin-17 ; Sclerosis/pathology* ; Transforming Growth Factor beta ; Mesentery/pathology* ; RNA, Messenger/metabolism* ; Blood Pressure

In the present study, the contents of seven active components [genipinic acid(GA), protocatechuic acid(PCA), neochlorogenic acid(NCA), chlorogenic acid(CA), cryptochlorogenic acid(CCA),(+)-pinoresinol di-O-β-D-glucopyranosid(PDG), and(+)-pinoresinol 4'-O-β-D-glucopyranoside(PG)] of Eucommiae Cortex in aortic vascular endothelial cells of spontaneously hypertensive rats(SHR) were simultaneously determined by ultra-high liquid chromatography-triple quadrupole mass spectrometry(UPLC-MS/MS). The qualified SHR models were selected. The primary aortic endothelial cells(VECs) of rats were separated and cultured by ligation and adherence, followed by subculture. After successful identification, an UPLC-MS/MS method for simultaneously determining the contents of GA, PCA, NCA, CA, CCA, PDG, PG in seven components of Eucommiae Cortex in VECs was established, including specificity, linearity, matrix effect, recovery, accuracy, precision and stability. The established method had the lo-west limit of quantification of 0.97-4.95 μg·L~(-1), accuracy of 87.26%-109.6%, extraction recovery of 89.23%-105.3%, matrix effect of 85.86%-106.2%, and stability of 86.00%-112.5%. Therefore, the established accurate UPLC-MS/MS method could rapidly and simultaneously determine the contents of the seven active components of Eucommiae Cortex in VECs of SHRs, which provided a refe-rence for the study of cellular pharmacokinetics of active components of Eucommiae Cortex extract.
Rats ; Animals ; Rats, Inbred SHR ; Chromatography, Liquid ; Chromatography, High Pressure Liquid/methods* ; Endothelial Cells ; Tandem Mass Spectrometry/methods*

OBJECTIVE: To investigate whether the antihypertensive mechanism of electroacupuncture (EA) is associated with attenuating phenotype transformation of vascular smooth muscle cells (VSMCs) via phosphoinositide3-kinase (PI3K)/protein kinase B (Akt) and mitogen-activated protein kinase (MAPK) signaling pathways. METHODS: Eight Wistar-ktoyo (WKY) rats were set as normal blood pressure group (normal group). A total of 32 spontaneous hypertensive rats (SHRs) were randomly divided into 4 groups using random number tables: a model group, an EA group, an EA+PI3K antagonist group (EA+P group), and an EA+p38 MAPK agonist+extracellular signal-regulated kinase (ERK) agonist group (EA+M group) (n=8/group). SHRs in EA group, EA+P group and EA+M group received EA treatment 5 sessions per week for continuous 4 weeks, while rats in the normal and model groups were bundled in same condition. The systolic blood pressure (SBP), diastolic blood pressure (DBP), and mean arterial pressure (MAP) of each rat was measured at 0 week and the 4th week. After 4-week intervention, thoracic aorta was collected for hematoxylin-eosin (HE) staining, immunohistochemistry [the contractile markers α-smooth muscle actin (α-SMA) and calponin and the synthetic marker osteopontin (OPN)] and Western blot [α-SMA, calponin, OPN, PI3K, phosphorylated-Akt (p-Akt), Akt, p-p42/44 ERK, total p42/44 ERK, p-p38 MAPK and total p38 MAPK]. RESULTS: EA significantly reduced SBP, DBP and MAP (P<0.01). HE staining showed that the wall thickness of thoracic aorta in EA group was significantly decreased (P<0.01). From results of immunohistochemistry and Western blot, EA increased the expression of α-SMA and calponin, and decreased the expression of OPN (P<0.01). In addition, the expression of PI3K and p-Akt increased (P<0.01), while the expression of p-p42/44 ERK and p-p38 MAPK decreased in EA group (P<0.01). However, these effects were reversed by PI3K antagonist, p38 MAPK agonist and ERK agonist. CONCLUSIONS EA was an effective treatment for BP management. The antihypertensive effect of EA may be related with inhibition of phenotypic transformation of VSMCs, in which the activation of PI3K/Akt and the repression of MAPK pathway were involved.
Animals ; Electroacupuncture ; Extracellular Signal-Regulated MAP Kinases/metabolism* ; MAP Kinase Signaling System ; Muscle, Smooth, Vascular ; Phenotype ; Phosphatidylinositol 3-Kinases/metabolism* ; Proto-Oncogene Proteins c-akt/metabolism* ; Rats ; Rats, Inbred SHR