Protective HSP70 Induction by Z-Ligustilide against Oxygen-Glucose Deprivation Injury via Activation of the MAPK Pathway but Not of HSF1

Using single cell atlas data to reconstruct regulatory networks

Inference of global gene regulatory networks from omics data is a long-term goal of systems biology. Most methods developed for inferring transcription factor (TF)-gene interactions either relied on a small dataset or used snapshot data which is not suitable for inferring a process that is inherently temporal. Here, we developed a new computational method that combines neural networks and multi-task learning to predict RNA velocity rather than gene expression values. This allows our method to overcome many of the problems faced by prior methods leading to more accurate and more comprehensive set of identified regulatory interactions. Application of our method to atlas scale single cell data from 6 HuBMAP tissues led to several validated and novel predictions and greatly improved on prior methods proposed for this task.

Transcriptomic Response under Heat Stress in Chickens Revealed the Regulation of Genes and Alteration of Metabolism to Maintain Homeostasis

Simple Summary

With the increased global temperature, the threat from climate change has already affected the livestock industry. Exposure to heat stress is a major factor responsible for impacts on the overall livestock production, which ultimately results in economic losses. With no exception, poultry is among the most vulnerable livestock to environmental stress. Hence, a comprehensive study is required to understand the molecular mechanisms and to improve the breeding program to overcome economic losses. Therefore, we investigated growth related phenotypes and performed transcriptome analysis to understand the heat stress response in chickens. Animal experiments were designed with two groups, which were kept at 21 and 33 °C for 2 weeks as the control and treatment groups. The transcriptome analysis used blood samples from each chicken. In this study, we identified a total of 245 differentially expressed genes (DEGs) with important roles in various biological processes, such as cell protection, energy conversion in the mitochondria, and protein quality control. The results indicate that the heat stress environment regulates genes and alter the metabolism to adjust for the heat environment in chickens. These findings could be useful to help understand the heat stress response in poultry.

Abstract

Chicken is important livestock that serves as a vital food source which remain largely affected by heat stress. Therefore, we performed the transcriptome analysis to help understand the mechanisms of heat stress response in chickens. In the animal experiments, we grouped them into a normal and severe at 21 and 33 °C, with identified physiologic parameters for 2-weeks. Subsequently, RNA-seq analysis was performed to identify DEGs with a false discovery rate < 0.05 and a fold change ≥ 1.5. In the physiological parameters, we observed average daily gain was declined, rectal temperature and respiration rate was increased in severe group. Among total 245 DEGs, 230 and 15 genes were upregulated and downregulated, respectively. In upregulated DEGs, HSPs, MYLK2, and BDKRB1 genes were identified as key genes in heat stress. The KEGG pathway analysis showed involvement in the ATP metabolic process, MAPK signaling pathway and calcium signaling pathway with related protein processing and synthesis. In conclusion, with induced heat stress, such changes in physiologic parameters alter the neuroendocrine system, and we observed that the heat stress environment regulates such Heat shock protein genes to protect the cells and proteins from an altered metabolism. These findings provide a more comprehensive understanding of the heat stress response in poultry.

Antidepressant-like effects of Z-ligustilide on chronic unpredictable mild stress-induced depression in rats

Depression is a significant public health issue and its neuropathogenesis is associated with the dysfunction of progesterone and allopregnanolone biosynthesis. Z-ligustilide (LIG), one of the main components of the herb Angelica sinensis (Oliv.) Diels (AS), is reported to have antidepressant activities. The present study aimed to evaluate the antidepressant-like effects of LIG via behavioral tests and to measure the levels of progesterone and allopregnanolone in the prefrontal cortex and hippocampus. The results demonstrated that LIG (20 and 40 mg/kg) exerted antidepressant-like effects, confirmed by increased mobility, locomotion, rearing frequency and preference to sucrose. Furthermore, the levels of progesterone and allopregnanolone in the prefrontal cortex and hippocampus were markedly increased following treatment with LIG (20 and 40 mg/kg), indicating that both neurosteroids could serve a significant role in the antidepressant-like effects of LIG.

Effect of heat shock protein 70 modulators on the development of morphine analgesic tolerance in rats

The clinical use of opioid analgesics, such as morphine, is limited by analgesic tolerance, molecular mechanism of which is not well understood. Recently, molecular chaperone heat shock protein 70 (Hsp70) has been demonstrated to play important roles in morphine-induced neuroadaptation. Here, we focused on the involvement of Hsp70 in the development of analgesic tolerance to morphine. Rats were treated with morphine (5, 10, 20 mg/kg, subcutaneously) or saline once daily for 10 consecutive days. Hsp70 modulator N-formyl-3, 4-methylenedioxybenzylidine-γ-butyrolactam [KNK437, 100 mg/kg, intraperitoneally (i.p.)], geranylgeranylacetone (500 mg/kg, i.p.) or pifithrin-μ (20 mg/kg, i.p.) was administered before morphine (10 mg/kg, subcutaneously)/saline treatment. Analgesic effect of morphine was measured using the tail-flick latency test, and Hsp70 protein expression was examined by western blot. Analgesic effect of morphine decreased gradually with the increase in the number of days of morphine injection, indicating development of analgesic tolerance. A significant increase of Hsp70 expression in the periaqueductal gray was observed during the development of analgesic tolerance after repeated morphine injections. The development of morphine analgesic tolerance was suppressed by pre-treatment with Hsp70 transcriptional inhibitor KNK437 or functional antagonist pifithrin-μ, while promoted by pre-treatment with Hsp70 transcriptional inducer geranylgeranylacetone. Our results demonstrated that the development of morphine analgesic tolerance was dual regulated by Hsp70 modulators, suggesting Hsp70 as an interesting and new target for preventing the development of opioid analgesic tolerance.

Neuroprotection: Targeting Multiple Pathways by Naturally Occurring Phytochemicals

With the increase in the expectancy of the life span of humans, neurodegenerative diseases (NDs) have imposed a considerable burden on the family, society, and nation. In defiance of the breakthroughs in the knowledge of the pathogenesis and underlying mechanisms of various NDs, very little success has been achieved in developing effective therapies. This review draws a bead on the availability of the nutraceuticals to date for various NDs (Alzheimer's disease, Parkinson's disease, Amyotrophic lateral sclerosis, Huntington's disease, vascular cognitive impairment, Prion disease, Spinocerebellar ataxia, Spinal muscular atrophy, Frontotemporal dementia, and Pick's disease) focusing on their various mechanisms of action in various in vivo and in vitro models of NDs. This review is distinctive in its compilation to critically review preclinical and clinical studies of the maximum phytochemicals in amelioration and prevention of almost all kinds of neurodegenerative diseases and address their possible mechanism of action. PubMed, Embase, and Cochrane Library searches were used for preclinical studies, while ClinicalTrials.gov and PubMed were searched for clinical updates. The results from preclinical studies demonstrate the efficacious effects of the phytochemicals in various NDs while clinical reports showing mixed results with promise for phytochemical use as an adjunct to the conventional treatment in various NDs. These studies together suggest that phytochemicals can significantly act upon different mechanisms of disease such as oxidative stress, inflammation, apoptotic pathways, and gene regulation. However, further clinical studies are needed that should include the appropriate biomarkers of NDs and the effect of phytochemicals on them as well as targeting the appropriate population.

Ligustilide protects PC12 cells from oxygen-glucose deprivation/reoxygenation-induced apoptosis via the LKB1-AMPK-mTOR signaling pathway

Autophagy has been shown to have a protective effect against brain damage. Ligustilide (LIG) is a bioactive substance isolated from Ligusticum chuanxiong, a traditional Chinese medicine. LIG has a neuroprotective effect; however, it is unclear whether this neuroprotective effect involves autophagy. In this study, PC12 cells were treated with 1 × 10^–5–1 × 10^–9 M LIG for 0, 3, 12 or 24 hours, and cell proliferation was evaluated using the 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assay. Treatment with 1 × 10^–6 M LIG for 3 hours had the greatest effect on cell proliferation, and was therefore used for subsequent experiments. PC12 cells were pre-treated with 1 × 10^–6 M LIG for 3 hours, cultured in 95% N₂/5% CO₂ in Dulbecco’s modified Eagle’s medium without glucose or serum for 4 hours, and then cultured normally for 16 hours, to simulate oxygen-glucose deprivation/reoxygenation (OGD/R). Cell proliferation was assessed with the MTS assay. Apoptosis was detected by flow cytometry. The expression levels of apoptosis-related proteins, Bcl-2 and Bax, autophagy-related proteins, Beclin 1 and microtubule-associated protein l light chain 3B (LC3-II), and liver kinase B1 (LKB1)-5′-adenosine monophosphate-activated protein kinase (AMPK)-mammalian target of rapamycin (mTOR) signaling pathway-related proteins were assessed by western blot assay. Immunofluorescence staining was used to detect LC3-II expression. Autophagosome formation was observed by electron microscopy. LIG significantly decreased apoptosis, increased Bcl-2, Beclin 1 and LC3-II expression, decreased Bax expression, increased LC3-II immunoreactivity and the number of autophagosomes, and activated the LKB1-AMPK-mTOR signaling pathway in PC12 cells exposed to OGD/R. The addition of the autophagy inhibitor 3-methyladenine or dorsomorphin before OGD/R attenuated the activation of the LKB1-AMPK-mTOR signaling pathway in cells treated with LIG. Taken together, our findings show that LIG promotes autophagy and protects PC12 cells from apoptosis induced by OGD/R via the LKB1-AMPK-mTOR signaling pathway.

Role of MAPKs in HSP70's Protection against Heat Stress-Induced Injury in Rat Small Intestine

Aim

To evaluate the role of heat shock protein 70 (HSP70) on the MAPK pathway activation with quercetin treatment and its protection against small intestine impairments of heat stressed rats.

Methods

Forty-eight male Sprague-Dawley rats aged 6 weeks were randomized to three groups (n=16/group), namely, control (CON), heat stress (HS), and heat stress + quercetin (HQ). The experiment lasted for 14 days with daily 50 min of heat stress treatment (43°C) for the HS and HQ groups. Rats of HQ group were intragastrically given 0.5 ml quercetin solution (50 mg/kg body weight) before the heat stress treatment. Half of the animals were sacrificed on day 7 and the rest on day 14 for tissue sampling. Intestinal morphology, small intestine morphology and permeability, protein expression of HSP70, phosphorylation of extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK), p38 mitogen-activated protein kinase (MAPK), and caspase-3 activity were examined.

Results

Heat stress caused morphological damage to the small intestine and increased intestinal permeability. HSP70 expression and MAPK activity in the small intestine were increased by heat stress. Inhibition of HSP70 by quercetin did not change intestinal permeability compared with the HS group but aggravated intestinal injury and affected the activation of MAPKs and caspase-3.

Conclusions

HSP70 may modulate stress-activated signaling and acts in a protective manner via MAPK signaling. Affecting HSP70 protective mechanisms could be useful for protection against heat stress-induced injury in rat small intestine.

Z-Ligustilide Exerted Hormetic Effect on Growth and Detoxification Enzymes of Spodoptera litura Larvae

Plants have evolved a variety of phytochemicals to defense insect feeding, whereas insects have also evolved diverse detoxification enzymes, which are adaptively induced as a prosurvival mechanism. Herein, Z-ligustilide in Ligusticum chuanxiong Hort. was found to exhibit a similar trend in the accumulation from December to May as the occurrence of Spodoptera litura (Fabricius) larvae. Importantly, S. litura larvae feeding enhanced Z-ligustilide level in the stem and leaf (p < 0.01). Moreover, Z-ligustilide ranging from 1 to 5 mg·g⁻¹ exhibited remarkable larvicidal activity, antifeedant activity, and growth inhibition against S. litura larvae. The LC₅₀ values of larvicidal activity for phthalides in L. chuanxiong were compared as follows: Z-ligustilide > levistilide A > senkyunolide A > 3-butylidenephthalide > senkyunolide I, implicating the critical role of conjugated structure. Notably, there was a biphasic dose response for glutathione S-transferase (GST), cytochrome P450 (CYP) 450, Acetylcholinesterase (AChE), and Carboxylesterase (CarE) activities and GSTs1, cytochrome P450 (CYP) 4S9, and CYP4M14 mRNA expression. Particularly, low dose (0.1 mg·g⁻¹) of Z-ligustilide conferred the resistance of S. litura larvae against chlorpyrifos (p < 0.05). Together, our data suggest that Z-ligustilide may function in a hormetic way in the chemical defense of L. chuanxiong against S. litura larvae.

Capture of anti-coagulant active ingredients from Moutan Cortex by platelet immobilized chromatography and evaluation of anticoagulant activity in rats

Moutan Cortex (MC) is a well-known Chinese medicine for promoting blood circulation and relieving blood stasis. The intent of this study was to evaluate the anticoagulant activity of MC and capture the bioactive compounds by platelet immobilized chromatography. Sprague Dawley (SD) rats were randomly divided into the control group, aspirin group and MC group (1.25, 2.5, 5g/kg/d). Coagulation system and platelet activity were investigated to evaluate the anti-coagulation effect of MC. The effective components of MC were captured by platelet immobilized chromatography. High performance liquid chromatography-diode array detection (HPLC-DAD) and liquid chromatography coupled to electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) analysis were used to identify the binding ingredients. Meanwhile, the efficacy of active ingredients was assessed through inhibiting platelet adhesion and regulating the expression of platelet related proteins. Principal findings showed that 2.5g/kg/d MC significantly prolonged thrombin time (TT) and 5g/kg/d MC significantly prolonged TT and prothrombin time (PT). MC exhibited an inhibitory potency on adenosine diphosphate-induced platelet aggregation. Four active compounds were found by platelet immobilized chromatography including oxypaeoniflorin, tetragalloylglucose, pentagalloyl glucose and benzoylpaeoniflorin; these active ingredients significantly up-regulated the expression of hsp-70 and coronin-1B, reduced the ratio of adhesion platelets. These results suggest that MC markedly promoted blood circulation and relieved blood stasis by inhibiting platelet activation, as an anti-coagulant, elucidating its potential capacity to treat cardiovascular diseases.

Intranasal Pretreatment with Z-Ligustilide, the Main Volatile Component of Rhizoma Chuanxiong, Confers Prophylaxis against Cerebral Ischemia via Nrf2 and HSP70 Signaling Pathways

Z-Ligustilide (Z-LIG) is a major component in Rhizoma Chuanxiong, which has been traditionally used as a health food supplement for the prevention of cerebrovascular disease in China. This study investigates the ability of intranasal Z-LIG pretreatment to enhance protection against neuronal damage in rats with middle cerebral artery occlusion (MCAO) and the role of cellular stress response mechanisms Nrf2 and HSP70. Z-LIG significantly mitigated infarct volume, neurological dysfunction, blood-brain barrier disruption, and brain edema (p < 0.01). Moreover, Z-LIG prevented the loss of collagen IV, occludin, and ZO-1 (p < 0.05) and decreased MMP-2 and -9 levels (p < 0.01). Meanwhile, Z-LIG up-regulated NQO1 and HSP70. Notably, blockage of Nrf2-driven transcription or down-regulation of HSP70 remarkably attenuated the preventive effect of Z-LIG (p < 0.05). Together, intranasal delivery of Z-LIG enhanced protection against ischemic injury via Nrf2 and HSP70 signaling pathways and has prophylactic potential in the population at high risk of stroke.

Senkyunolide I attenuates oxygen-glucose deprivation/reoxygenation-induced inflammation in microglial cells

Over-activated microglia during stroke has been documented to aggravate brain damage. Our previous studies showed that senkyunolide I (SEI) exerted anti-inflammatory effects against endotoxin insult in vitro and ameliorative effects on cerebral ischemia/reperfusion (I/R) injury in vivo. Using oxygen-glucose deprivation/reoxygenation (OGD/R) to mimic stroke, we here investigated the anti-inflammatory effect of SEI on microglial cells and explored the underlying mechanisms. OGD for 3h followed by reoxygenation for 12h significantly enhanced the release of pro-inflammatory cytokines and expressions of inflammation-related enzymes in BV-2 cells, which was inhibited by pretreatment with SEI. To elucidate the mechanisms, we studied its effect on upstream signaling pathways. It was found that SEI suppressed the activation of NF-κB pathway induced by OGD/R and the MAPK pathway was shown not to be involved. Furthermore, SEI significantly down-regulated TLR4/MyD88 pathway with specifically improving inducible Hsp70 level through increasing HSF-1/DNA binding activity, and these regulations responsive to SEI were attenuated by transfecting Hsp70 siRNA and HSF-1 decoy ODNs. Additionally, SEI exerted similar influence on Hsp70/TLR4/NF-κB pathway in rat primary microglial cells. The results suggested that SEI had a potent effect against stroke-induced neuroinflammation through suppressing the TLR4/NF-κB pathway by up-regulating Hsp70 dependent on HSF-1.

Curcumol Suppresses Breast Cancer Cell Metastasis by Inhibiting MMP-9 Via JNK1/2 and Akt-Dependent NF-κB Signaling Pathways

Curcumolhas been reported to possess antitumor activity. However, its effect and mechanisms against tumor metastasis are still unclear. This study is to investigate the inhibitory effect of curcumol on breast cancer cell metastasis and elucidate the underlying molecular mechanisms. Our results showed that noncytotoxicity was caused by curcumol within 10 to 40 µg/mL in MDA-MB-231 and 4T1 cells for 24 hours, whereas sustained treatment with curcumol for 14 days significantly suppressed the clonogenic activity of cells. Importantly, curcumol at noncytotoxic concentrations suppressed the migration ability of both MDA-MB-231 and 4T1 cells. Moreover, curcumol suppressed the migration and invasion of MDA-MB-231 cells in the Boyden chamber migration and invasion assay and inhibited the adhesion of MDA-MB-231 cells onto the matrigel. Further investigations revealed that curcumol decreased the enzyme activity and protein expression of matrix metalloproteinase (MMP-9) in MDA-MB-231 cells. Moreover, curcumol inhibited the activation of c-Jun N-terminal kinase (JNK) 1/2 and Akt (Ser473). Meanwhile, it also inhibited the nuclear translocation and transcriptional activity of nuclear factor κB (NF-κB). Furthermore, JNK inhibitor SP600125 and Akt (Ser473) inhibitor LY294002 enhanced the inhibition of curcumol on NF-κB p65 nuclear translocation. Finally, supplementation with SP600125, LY294002, or NF-κB inhibitor Ammonium pyrrolidinedithiocarbamate (PDTC) significantly enhanced the inhibitory effect of curcumol on MMP-9 expression and cell migration, invasion, and adhesion in MDA-MB-231 cells. Our findings provide evidence for the suppression of breast cancer cell metastasis by curcumol and suggest that the inhibition of MMP-9 via JNK1/2 and Akt (Ser473)-dependent NF-κB signaling pathways may be the underlying mechanisms.