Auraptene Enhances Junction Assembly in Cerebrovascular Endothelial Cells by Promoting Resilience to Mitochondrial Stress through Activation of Antioxidant Enzymes and mtUPR

Mitochondrial homeostasis in odontoblast: Physiology, pathogenesis and targeting strategies

Caries and pulpitis remain a major global disease burden and affect the quality of life of patients. Odontoblasts are key players in the progression of caries and pulpitis, not only secreting and mineralizing to form dentin, but also acting as a wall of defense to initiate immune defenses. Mitochondrion is an information processor for numerous cellular activities, and dysregulation of mitochondrion homeostasis not only affects cellular metabolism but also triggers a wide range of diseases. Elucidating mitochondrial homeostasis in odontoblasts can help deepen scholars' understanding of odontoblast-associated diseases. Articles on mitochondrial homeostasis in odontoblasts were evaluated for information pertinent to include in this narrative review. This narrative review focused on understanding the complex interplay between mitochondrial homeostasis in odontoblasts under physiological and pathological conditions. Furthermore, mitochondria-centered therapeutic strategies (including mitochondrial base editing, targeting platforms, and mitochondrial transplantation) were emphasized by resolving key genes that regulate mitochondrial function. Mitochondria are involved in odontoblast differentiation and function, and act as mitochondrial danger-associated molecular patterns (mtDAMPs) to mediate odontoblast pathological progression. Novel mitochondria-centered therapeutic strategies are particularly attractive as emerging therapeutic approaches for the maintenance of mitochondrial homeostasis. It is expected to probe key events of odontoblast differentiation and advance the clinical resolution of dentin formation and mineralization disorders and odontoblast-related diseases.

Synergistic effects of auraptene and 17-β estradiol on traumatic brain injury treatment: oxidant/antioxidant status, inflammatory cytokines and pathology

OBJECTIVE

Despite significant advances that have been made in the treatment of traumatic brain injury (TBI), it remains a global health issue. This study aimed to investigate the synergistic effects of 17-β estradiol (E2) and auraptene (AUR) on TBI treatment.

METHODS

In total, 70 adult male Wistar rats were divided randomly into ten main groups: Sham, TBI, TBI + DMSO, TBI + AUR (4 mg/kg), TBI + AUR (8 mg/kg), TBI + AUR (25 mg/kg), TBI + E2 group, TBI + AUR (4 mg/kg) + E2 group, TBI + AUR (8 mg/kg) + E2 group and TBI + AUR (25 mg/kg) + E2 group. Diffuse TBI was caused by the Marmarou process in male rats. The brain's tissues were harvested to check the parameters of oxidative stress and levels of inflammatory cytokine.

RESULTS

The finding revealed that TBI induced a significant increase in brain edema, pro-inflammatory cytokines and oxidant levels [MDA and NO], and also a decrease in the brain's antioxidant biomarkers [GPx, SOD]. We also found that E2 and AUR (25 mg/kg) significantly preserved the levels of these biomarkers. The combination of AUR concentrations and E2 showed that this treatment efficiently preserved the levels of these biomarkers. Furthermore, the combination of E2 and AUR (25 mg/kg) c could cause the most effective synergistic interaction.

CONCLUSION

AUR could act synergistically with E2 to treat brain injury complications.

KLF10 knockdown negatively regulates CTRP3 to improve OGD/R-induced brain microvascular endothelial cell injury and barrier dysfunction through Nrf2/HO-1 signaling pathway

Ischemic stroke seriously endangers human health and even death. This study aimed to investigate the role of KLF10/CTRP3 in oxygen-glucose deprivation/reperfusion (OGD/R)-induced brain microvascular endothelial cells injury, as well as the regulatory effects of the Nrf2/HO-1 signaling pathway. OGD/R-induced human microvascular endothelial cells (hBMECs) were used to simulate the model of cerebral ischemia-reperfusion (I/R) injury. The expression of KLF10/CTRP3 in OGD/R-induced hBMECs as well as the transfection efficiency were all detected by RT-qPCR and western blot. The interaction of KLF10 and CTRP3 was confirmed by dual-luciferase reporter assay and chromatin immunoprecipitation (ChIP). The viability, apoptosis and endothelial permeability of OGD/R-induced hBMECs was detected by CCK-8, TUNEL and FITC-Dextran assay kit. The capacity of cell migration was assessed by wound healing assay. The expression of apoptosis related proteins, oxidative stress levels and tight junction proteins was also detected. As a result, the expression of KLF10 was increased in OGD/R-induced hBMECs and downregulation of KLF10 could promote the viability, migration and suppress the apoptosis, oxidative stress and endothelial permeability by downregulating the expression of caspase 3, Bax, cleaved PARP, ROS, MDA, and upregulating the expression of Bcl-2, SOD, GSH-Px, ZO-1, occludin, claudin-5. Nrf2/HO-1 signaling pathway was inhibited in OGD/R-induced hBMECs, which was activated by downregulation of KLF10. KLF10 was demonstrated to be combined with CTRP3 and KLF10 inhibited transcription of CTRP3 in hBMECs. The above changes affected by downregulation of KLF10 could be reversed by the interference with CTRP3. In conclusion, KLF10 knockdown improved OGD/R-induced brain microvascular endothelial cell injury and barrier dysfunction through the activation of Nrf2/HO-1 signaling pathway, which was weakened by the downregulation of CTRP3.

Effects of Citrus kawachiensis Peel in Frailty-like Model Mice Induced by Low Protein Nutrition Disorders

"Frailty" caused by a decline in physiological reserve capacity, chronic inflammation, and oxidative stress in the elderly has recently become a major social issue. The present study examined the effects of the peel of Citrus kawachiensis (CK), which exhibits anti-inflammatory, antioxidant, and pro-neurogenesis activities in frailty-like model mice. Male C57BL/6 mice (15 weeks old) were fed an 18% protein diet (CON), a 2.5% protein diet (PM), and PM mixed with 1% dried CK peel powder for approximately 1 month. Mice were euthanized 2 or 8 days after a single intraperitoneal administration of lipopolysaccharide (LPS) and tissues were dissected. Among peripheral tissues, muscle weight, liver weight, and blood glucose levels were significantly higher in the PM-LPS-CK group than in the PM-LPS group. In the behavioral analysis, locomotive activity was significantly lower in the PM-LPS group than in the PM group. The reduction in locomotive activity in the PM-LPS-CK group was significantly smaller than that in the PM-LPS group. The quantification of microglia in the hippocampal stratum lacunosum-moleculare revealed that increases in the PM-LPS group were significantly suppressed by the dried CK peel powder. Furthermore, the quantification of synaptic vesicle membrane proteins in the hippocampal CA3 region showed down-regulated expression in the PM-LPS group, which was significantly ameliorated by the administration of the dried CK peel powder. Collectively, these results suggest that CK inhibits inflammation and oxidative stress induced by PM and LPS in the central nervous system and peripheral tissue. Therefore, C. kawachiensis is highly effective against "frailty".

Mitochondrial Modulators: The Defender

Mitochondria are widely considered the "power hub" of the cell because of their pivotal roles in energy metabolism and oxidative phosphorylation. However, beyond the production of ATP, which is the major source of chemical energy supply in eukaryotes, mitochondria are also central to calcium homeostasis, reactive oxygen species (ROS) balance, and cell apoptosis. The mitochondria also perform crucial multifaceted roles in biosynthetic pathways, serving as an important source of building blocks for the biosynthesis of fatty acid, cholesterol, amino acid, glucose, and heme. Since mitochondria play multiple vital roles in the cell, it is not surprising that disruption of mitochondrial function has been linked to a myriad of diseases, including neurodegenerative diseases, cancer, and metabolic disorders. In this review, we discuss the key physiological and pathological functions of mitochondria and present bioactive compounds with protective effects on the mitochondria and their mechanisms of action. We highlight promising compounds and existing difficulties limiting the therapeutic use of these compounds and potential solutions. We also provide insights and perspectives into future research windows on mitochondrial modulators.

Protection of Mitochondrial Potential and Activity by Oxyprenylated Phenylpropanoids

A series of five naturally occurring oxyprenylated phenylpropanoids, namely, the coumarins auraptene (7-geranyloxycoumarin) 1 and 7-isopentenyloxycoumarin 2, and the coumaric acid and ferulic acid derivatives, 4'-isopentenyloxycoumaric acid 3, boropinic acid 4, and 4'-geranyloxyferulic acid 5 were tested for their effects on mitochondrial functionality using the organophosphate pesticides glyphosate and chlorpyrifos, and resveratrol, as the reference. While not showing an appreciable in vitro antioxidant activity, and virtually no or a little effect on the viability of non-cancer cell lines BEAS-2B and SHSY-5Y, all phytochemicals exhibited a marked protective effect on mitochondrial potential and activity, with values that were comparable to resveratrol. Auraptene 1 and 7-isopentenyloxycoumarin 2 were seen to be the most effective secondary metabolite to this concern, in particular in being able to completely abolish the decrease of mitochondrial potential induced by increasing concentration of both glyphosate and chlorpyrifos. All the compounds tested also exhibited a protective effect on mitochondrial activity. The potency displayed will shed more light on the molecular basis of the beneficial effects of auraptene, 7-isopentenyloxycoumarin, and structurally related oxyprenylated phenylpropanoids reported to date in the literature.

mtUPR Modulation as a Therapeutic Target for Primary and Secondary Mitochondrial Diseases

Mitochondrial dysfunction is a key pathological event in many diseases. Its role in energy production, calcium homeostasis, apoptosis regulation, and reactive oxygen species (ROS) balance render mitochondria essential for cell survival and fitness. However, there are no effective treatments for most primary and secondary mitochondrial diseases to this day. Therefore, new therapeutic approaches, such as the modulation of the mitochondrial unfolded protein response (mtUPR), are being explored. mtUPRs englobe several compensatory processes related to proteostasis and antioxidant system mechanisms. mtUPR activation, through an overcompensation for mild intracellular stress, promotes cell homeostasis and improves lifespan and disease alterations in biological models of mitochondrial dysfunction in age-related diseases, cardiopathies, metabolic disorders, and primary mitochondrial diseases. Although mtUPR activation is a promising therapeutic option for many pathological conditions, its activation could promote tumor progression in cancer patients, and its overactivation could lead to non-desired side effects, such as the increased heteroplasmy of mitochondrial DNA mutations. In this review, we present the most recent data about mtUPR modulation as a therapeutic approach, its role in diseases, and its potential negative consequences in specific pathological situations.

The Antioxidant Auraptene Improves Aged Oocyte Quality and Embryo Development in Mice

Decrease in quality of postovulatory aged oocytes occurs due to oxidative stress and leads to low fertilization and development competence. It is one of the main causes that exerting detrimental effect on the success rate in assisted reproductive technology (ART). Auraptene (AUR), a citrus coumarin, has been reported to possess an antioxidant effects in other tissues. In this study, we aimed to confirm the potential of AUR to delay the oocyte aging process by alleviating oxidative stress. Superovulated mouse oocytes in metaphase of second meiosis (MII) were exposed to 0, 1 or 10 μM AUR for 12 h of in vitro aging. AUR addition to the culture medium recovered abnormal spindle and chromosome morphology and mitigated mitochondrial distribution and mitochondrial membrane potential (ΔΨ) in aged oocytes. AUR-treated aged oocytes also showed suppressed oxidative stress, with lower reactive oxygen species (ROS) levels, higher glutathione (GSH) levels and increased expression of several genes involved in antioxidation. Furthermore, AUR significantly elevated the fertilization and embryo developmental rates. Oocytes aged with 1 μM AUR exhibited morphokinetics that were very similar to those of the control group. Altogether, these data allowed us to conclude that AUR improved the quality of aged oocytes and suggest AUR as an effective clinical supplement candidate to prevent postovulatory aging.