Crocin attenuation of neurological deficits in a mouse model of intracerebral hemorrhage

Crocin molecular signaling pathways at a glance: A comprehensive review

Crocin is a hydrophilic carotenoid that is synthesized in the flowers of the Crocus genus. Numerous in vitro and in vivo research projects have been published about the biological and pharmacological properties and toxicity of crocin. Crocin acts as a memory enhancer, anxiolytic, aphrodisiac, antidepressant, neuroprotective, and so on. Here, we introduce an updated and comprehensive review of crocin molecular mechanisms based on previously examined and mentioned in the literature. Different studies confirmed the significant effect of crocin to control pathological conditions, including oxidative stress, inflammation, metabolic disorders, neurodegenerative disorders, and cancer. The neuroprotective effect of crocin could be related to the activation of phosphatidylinositol 3-kinase/protein kinase B (PI3K/AKT)/mammalian target of rapamycin (mTOR), Notch, and cyclic-AMP response element-binding protein signaling pathways. The crocin also protects the cardiovascular system through the inhibitory effect on toll-like receptors. The regulatory effect of crocin on PI3K/AKT/mTOR, AMP-activated protein kinase, mitogen-activated protein kinases (MAPK), and peroxisome proliferator-activated receptor pathways can play an effective role in the treatment of metabolic disorders. The crocin has anticancer activity through the PI3K/AKT/mTOR, MAPK, vascular endothelial growth factor, Wnt/β-catenin, and Janus kinases-signal transducer and activator of transcription suppression. Also, the nuclear factor-erythroid factor 2-related factor 2 and p53 signaling pathway activation may be effective in the anticancer effect of crocin. Finally, among signaling pathways regulated by crocin, the most important ones seem to be those related to the regulatory effect on the PI3K/AKT/mTOR pathway.

Crocins for Ischemic Stroke: A Review of Current Evidence

Crocins (CRs) and the related active constituents derived from Crocus sativus L. (Saffron) have demonstrated protective effects against cerebral ischemia and ischemic stroke, with various bioactivities including neuroprotection, anti-neuroinflammation, antioxidant, and cardiovascular protection. Among CRs, crocin (CR) has been shown to act on multiple mechanisms and signaling pathways involved in ischemic stroke, including mitochondrial apoptosis, nuclear factor kappa light chain enhancer of B cells pathway, S100 calcium-binding protein B, interleukin-6 and vascular endothelial growth factor-A. CR is generally safe and well-tolerated. Pharmacokinetic studies indicate that CR has poor bioavailability and needs to convert to crocetin (CC) in order to cross the blood-brain barrier. Clinical studies have shown the efficacy of saffron and CR in treating various conditions, including metabolic syndrome, depression, Alzheimer’s disease, and coronary artery disease. There is evidence supporting CR as a treatment for ischemic stroke, although further studies are needed to confirm their efficacy and safety in clinical settings.

GP-14 protects against severe hypoxia-induced neuronal injury through the AKT and ERK pathways and its induced transcriptome profiling alteration

Gypenosides are major bioactive ingredients of G. pentaphyllum. In our previous study, we found that gypenosides had neuroprotective effects against hypoxia-induced injury. In the current study, we focused on the protective effects of gypenoside-14 (GP-14), which is one of the newly identified bioactive components, on neuronal injury caused by severe hypoxia (0.3% O₂). The results showed that GP-14 pretreatment alleviated the cell viability damage and apoptosis induced by hypoxia in PC12 cells. Moreover, GP-14 pretreatment also attenuated primary neuron injuries under hypoxic conditions. Additionally, GP-14 pretreatment significantly ameliorated neuronal damage in the hippocampal region induced by high-altitude cerebral edema (HACE). At the molecular level, GP-14 pretreatment reversed the decreased activities of the AKT and ERK signaling pathways caused by hypoxia in PC12 cells and primary neurons. To comprehensively explore the possible mechanisms, transcriptome sequencing was conducted, and these results indicated that GP-14 could alter the transcriptional profiles of primary neuron. Taken together, our results suggest that GP-14 acts as a neuroprotective agent to protect against neuronal damage induced by severe hypoxia and it is a promising compound for the development of neuroprotective drugs.

Crocin Alleviates Intracerebral Hemorrhage-Induced Neuronal Ferroptosis by Facilitating Nrf2 Nuclear Translocation

Intracerebral hemorrhage (ICH) is the deadliest type of stroke. Oxidative stress was considered to play an important role in ICH-induced secondary injury. Crocin, the main compound isolated from Crocus sativus L., possesses a potential anti-oxidative function in many types of diseases including ICH. In the current study, the protective role of crocin in ICH-induced brain injury was investigated in the ICH model. The ICH-induced brain edema and neurological deficits were analyzed by brain edema measurement and neurological testing. The superoxide dismutase (SOD) and glutathione peroxidase (GSH-px) activity and the content of malondialdehyde (MDA) were assessed by a total superoxide dismutase assay kit. The expressions of ferroptosis-related genes were verified by quantitative real-time PCR (qPCR) and western blotting. The ICH-induced brain edema and neurological deficits were significantly decreased after treatment with crocin. Moreover, the SOD and GSH-px activities were obviously increased in the ICH with crocin-treated group compared with the ICH group, while the content of MDA was markedly decreased after treatment with crocin. Crocin inhibited ferroptosis of neuron cells, as evidenced by increased Fe²⁺ concentration and the expression of GPX4, FTH1, and SLC7A11. Mechanistically, crocin treatment increased the expression and nuclear translocation of Nrf2. Our data suggest that crocin alleviates intracerebral hemorrhage-induced neuronal ferroptosis by facilitating Nrf2 nuclear translocation.

Evaluation of the Effect of Crocin on Doxorubicin-Induced Cardiotoxicity

Despite newer advances in cancer treatment, chemotherapy is still one of the most widely used treatment strategies in this field. However, this treatment strategy faces major challenges. Doxorubicin (Dox) is an effective chemotherapeutic agent used to treat various cancers. However, several studies have shown that the use of Dox in therapeutic concentrations is associated with serious side effects, such as cardiac toxicity. The use of natural products in combination with chemotherapeutic agents to reduce side effects is a novel approach, and several studies have shown promising results. In this regard, we examined the effect of Crocin on doxorubicin-induced cardiotoxicity in rat and H9c2 cell line. The in vitro model on H9C2 cells and the in vivo models on rats were treated with doxorubicin. Cell viability, DNA damage, and apoptosis were measured in H9C2 cell line in the presence and absence of Crocin. Oxidative stress and various inflammatory parameters, as well as cardiac function tests, also were assessed in doxorubicin-induced cardiotoxicity animal model in the presence and absence of Crocin. Our results showed that Crocin can significantly decrease apoptosis in H9C2 cell line through a reduction in ROS production and DNA damages. Moreover, evaluation of the effect of Crocin on doxorubicin-induced cardiotoxicity animal model showed that Crocin also can significantly reduce oxidative stress and inflammatory parameters in the serum of the animals. Assessment of cardiac function revealed that Crocin has a significant protective effect against doxorubicin-induced cardiotoxicity in the animal model. Our data indicate that Crocin significantly attenuated doxorubicin-induced cardiotoxicity. Hence, Crocin could be potentially used as an adjuvant treatment in combination with Dox to reduce cardiotoxicity.

Rosuvastatin Nanomicelles Target Neuroinflammation and Improve Neurological Deficit in a Mouse Model of Intracerebral Hemorrhage

Background

Intracerebral hemorrhage (ICH), a devastating subtype of stroke, has a poor prognosis. However, there is no effective therapy currently available due to its complex pathological progression, in which neuroinflammation plays a pivotal role in secondary brain injury. In this work, the use of statin-loaded nanomicelles to target the neuroinflammation and improve the efficacy was studied in a mouse model of ICH.

Methods

Rosuvastatin-loaded nanomicelles were prepared by a co-solvent evaporation method using polyethylene glycol-poly(ε-caprolactone) (PEG-PCL) copolymer as a carrier. The prepared nanomicelles were characterized by transmission electron microscopy (TEM) and dynamic light scattering (DLS), and then in vitro and in vivo studies were performed.

Results

TEM shows that the nanomicelles are spherical with a diameter of about 19.41 nm, and DLS shows that the size, zeta potential, and polymer dispersity index of the nanomicelles were 23.37 nm, −19.2 mV, and 0.221, respectively. The drug loading content is 8.28%. The in vivo study showed that the nanomicelles significantly reduced neuron degeneration, inhibited the inflammatory cell infiltration, reduced the brain edema, and improved neurological deficit. Furthermore, it was observed that the nanomicelles promoted the polarization of microglia/macrophages to M2 phenotype, and also the expression of the proinflammatory cytokines, such as IL-1β and TNF-α, was significantly down-regulated, while the expression of the anti-inflammatory cytokine IL-10 was significantly up-regulated. The related mechanism was proposed and discussed.

Conclusion

The nanomicelles treatment suppressed the neuroinflammation that might contribute to the promoted nerve functional recovery of the ICH mouse, making it potential to be applied in clinic.

Saffron bioactives crocin, crocetin and safranal: effect on oxidative stress and mechanisms of action

Saffron (Crocus sativus L.) is used as a spice for its organoleptic characteristics related to its coloring and flavoring properties, and it has been also used in traditional medicine to treat various diseases. The main chemical components responsible for these properties are crocin, crocetin and safranal. These compounds have been shown to have a wide spectrum of biological activities, including several properties as antigenotoxic, antioxidant, anticancer, anti-inflammatory, antiatherosclerotic, antidiabetic, hypotensive, hypoglycemic, antihyperlipidemic, antidegenerative and antidepressant, among others. This review article highlights the antioxidant effects of these bioactive compounds to reduce reactive oxygen species (ROS) and the mechanisms of action involved, since there are a multitude of diseases related to oxidative stress and the generation of free radicals (FRs). Recent studies have shown that the effects of crocin, crocetin and safranal against oxidative stress include the reduction in lipid peroxidation (malondialdehyde [MDA] levels) and nitric oxide (NO) levels, and the increase in the levels of glutathione, antioxidant enzymes (superoxide dismutase [SOD], catalase (CAT) and glutathione peroxidase [GPx]) and thiol content. Therefore, due to the great antioxidant effects of these saffron compounds, it makes saffron a potential source of bioactive extracts for the development of bioactive ingredients, which can be used to produce functional foods.

Relationship of Serum Uric Acid to Hematoma Volume and Prognosis in Patients with Acute Supratentorial Intracerebral Hemorrhage

BACKGROUND

Oxidative stress and inflammation play important roles in the neuronal injury caused by intracerebral hemorrhage (ICH). Uric acid (UA), an important natural antioxidant, might reduce the neuronal injury caused by ICH. Delineating the relationship between UA and ICH will enhance our understanding of antioxidative mechanisms in recovery from ICH.

METHODS

We conducted a retrospective study of 325 patients with acute supratentorial ICH to investigate the relationship between serum UA levels and hematoma volumes and prognosis. A hematoma volume of ≥30 mL was defined as a large hematoma. An unfavorable outcome was defined as a modified Rankin scale score of 4-6 on day 30.

RESULTS

The serum UA level was significantly lower in the patients with a large hematoma volume (median, 306 μmol/L; 25th to 75th percentile, 243-411 μmol/L) than in those with a small hematoma volume (median, 357 μmol/L; 25th to 75th percentile, 271-442 μmol/L; P = 0.012). Similarly, the unfavorable outcome group had had lower serum UA levels (median, 309 vs. 363 μmol/L; P = 0.009) compared with the favorable outcome group. The results of the multivariate logistic analysis indicated that a lower serum UA level was associated with a larger hematoma volume (odds ratio, 0.996; P = 0.006) and an unfavorable outcome (odds ratio, 0.997; P = 0.030).

CONCLUSIONS

The results from the present study have indicated that in patients with acute supratentorial ICH, a low serum UA level might indicate that the patient has a large hematoma volume and might be a risk factor for a poor day 30 functional prognosis.

Injectable Gelatin Hydrogel Suppresses Inflammation and Enhances Functional Recovery in a Mouse Model of Intracerebral Hemorrhage

Intracerebral hemorrhage (ICH) is a devastating subtype of stroke with high morbidity and mortality. However, there is no effective therapy method to improve its clinical outcomes to date. Here we report an injectable gelatin hydrogel that is capable of suppressing inflammation and enhancing functional recovery in a mouse model of ICH. Thiolated gelatin was synthesized by EDC chemistry and then the hydrogel was formed through Michael addition reaction between the thiolated gelatin and polyethylene glycol diacrylate. The hydrogel was characterized by scanning electron microscopy, porosity, rheology, and cytotoxicity before evaluating in a mouse model of ICH. The in vivo study showed that the hydrogel injection into the ICH lesion reduced the neuron loss, attenuated the neurological deficit post-operation, and decreased the activation of the microglia/macrophages and astrocytes. More importantly, the pro-inflammatory M1 microglia/macrophages polarization was suppressed while the anti-inflammatory M2 phenotype was promoted after the hydrogel injection. Besides, the hydrogel injection reduced the release of inflammatory cytokines (IL-1β and TNF-α). Moreover, integrin β1 was confirmed up-regulated around the lesion that is positively correlated with the M2 microglia/macrophages. The related mechanism was proposed and discussed. Taken together, the injectable gelatin hydrogel suppressed the inflammation which might contribute to enhance the functional recovery of the ICH mouse, making it a promising application in the clinic.

Cognitive Protective Mechanism of Crocin Pretreatment in Rat Submitted to Acute High-Altitude Hypoxia Exposure

Inadequate oxygen availability at high altitude leads to oxidative stress, resulting in hippocampal neurodegeneration and memory impairment. In our previous study, we found that the cognitive dysfunction occurred when male SD rat was rapidly exposed to 4200 m of high altitude for 3 days. And we also found that crocin showed a cognitive protective effect under hypoxia by regulating SIRT1/PGC-1α pathways in rat's hippocampus. In this article, focused on factors related to SIRT1/PGC-1α pathways, we proposed to further elucidate crocin's pharmacological mechanism. Adult male Sprague-Dawley rats were randomly divided into five groups: control group, hypoxia group (rats were rapidly transported to high altitude of 4200 m for 72 h), and crocins+hypoxia groups (pretreatment with crocin of 25, 50, and 100 mg/kg/d for 3 days). The learning and memory ability was tested by Morris water maze analysis. Hippocampal histopathological changes were observed by HE staining and Nissl staining. The expression of NRF1, TFAM, Bcl-2, Bax, and caspase-3 was detected by immunohistochemistry, RT-PCR, and western blotting test. The contents of malondialdehyde (MDA), superoxide dismutase (SOD), glutathione (GSH), and glutathione peroxidase (GSHPx) were detected by the TBA, WST, and colorimetry method. Neuronal apoptosis was observed by TUNEL staining. After crocin pretreatment, the traveled distance was significantly reduced and the percentage of time in the target quadrant was significantly increased tested by Morris water maze. And neuronal damage in the hippocampus was also significantly ameliorated based on HE staining and Nissl staining. Furthermore, in hippocampus tissue, mitochondrial biosynthesis-related factors of NRF1, TFAM expression was increased; oxidative stress factors of SOD, GSH, and GSHPx expression level were increased, and MDA and glutathione disulfide (GSSG) level were decreased; antiapoptotic protein Bcl-2 expression was increased, and proapoptotic proteins Bax and caspase-3 expression were decreased, with a manner of crocin dose dependent. Therefore, the cognitive protective mechanism of crocin in rat under acute hypoxia was related to promoting mitochondrial biosynthesis, ameliorating oxidative stress injury, and decreasing neuronal apoptosis.