Theacrine, a purine alkaloid obtained from Camellia assamica var. kucha, attenuates restraint stress-provoked liver damage in mice

Mitochondrial sirtuin 3 and role of natural compounds: the effect of post-translational modifications on cellular metabolism

Sirtuins (SIRTs) are a family of proteins with enzymatic activity. In particular, they are a family of class III NAD+-dependent histone deacetylases and ADP-ribosyltransferases. NAD+-dependent deac(et)ylase activities catalyzed by sirtuin include ac(et)ylation, propionylation, butyrylation, crotonylation, manylation, and succinylation. Specifically, human SIRT3 is a 399 amino acid protein with two functional domains: a large Rossmann folding motif and NAD+ binding, and a small complex helix and zinc-binding motif. SIRT3 is widely expressed in mitochondria-rich tissues and is involved in maintaining mitochondrial integrity, homeostasis, and function. Moreover, SIRT3 regulates related diseases, such as aging, hepatic, kidney, neurodegenerative and cardiovascular disease, metabolic diseases, and cancer development. In particular, one of the most significant and damaging post-translational modifications is irreversible protein oxidation, i.e. carbonylation. This process is induced explicitly by increased ROS production due to mitochondrial dysfunction. SIRT3 is carbonylated by 4-hydroxynonenal at the level of Cys280. The carbonylation induces conformational changes in the active site, resulting in allosteric inhibition of SIRT3 activity and loss of the ability to deacetylate and regulate antioxidant enzyme activity. Phytochemicals and, in particular, polyphenols, thanks to their strong antioxidant activity, are natural compounds with a positive regulatory action on SIRT3 in various pathologies. Indeed, the enzymatic SIRT3 activity is modulated, for example, by different natural polyphenol classes, including resveratrol and the bergamot polyphenolic fraction. Thus, this review aims to elucidate the mechanisms by which phytochemicals can interact with SIRT3, resulting in post-translational modifications that regulate cellular metabolism.

Regulation of hepatocyte phospholipid peroxidation signaling by a Chinese patent medicine against psychological stress-induced liver injury

BACKGROUND

Psychological stress is associated with various diseases including liver dysfunction, yet effective intervention strategies remain lacking due to the unrevealed pathogenesis mechanism.

PURPOSE

This study aims to explore the relevance between BMAL1-controlled circadian rhythms and lipoxygenase 15 (ALOX15)-mediated phospholipids peroxidation in psychological stress-induced liver injury, and to investigate whether hepatocyte phospholipid peroxidation signaling is involved in the hepatoprotective effects of a Chinese patent medicine, Pien Tze Huang (PZH).

METHODS

Restraint stress models were established to investigate the underlying molecular mechanisms of psychological stress-induced liver injury and the hepatoprotective effects of PZH. Redox lipidomics based on liquid chromatography-tandem mass spectrometry was applied for lipid profiling.

RESULTS

The present study discovered that acute restraint stress could induce liver injury. Notably, lipidomic analysis confirmed that phospholipid peroxidation was accumulated in the livers of stressed mice. Additionally, the essential core circadian clock gene Brain and Muscle Arnt-like Protein-1 (Bmal1) was altered in stressed mice. Circadian disruption in mice, as well as BMAL1-overexpression in human HepaRG cells, also appeared to have a significant increase in phospholipid peroxidation, suggesting that stress-induced liver injury is closely related to circadian rhythm and phospholipid peroxidation. Subsequently, arachidonate 15-lipoxygenase (ALOX15), a critical enzyme that contributed to phospholipid peroxidation, was screened as a potential regulatory target of BMAL1. Mechanistically, BMAL1 promoted ALOX15 expression via direct binding to an E-box-like motif in the promoter. Finally, this study revealed that PZH treatment significantly relieved pathological symptoms of psychological stress-induced liver injury with a potential mechanism of alleviating ALOX15-mediated phospholipid peroxidation.

CONCLUSION

Our findings illustrate the critical role of BMAL1-triggered phospholipid peroxidation in psychological stress-induced liver injury and provide new insight into treating psychological stress-associated liver diseases by TCM intervention.

Comparative analysis of antioxidant activities and chemical compositions in the extracts of different edible parts from Camellia tetracocca Zhang (C. tetracocca) with two distinct color characteristics

The Camellia tetracocca Zhang is a rare and ancient plant, exclusively found in the vicinity of Puan County, Guizhou Province, China. According to leaf color, two distinct variations have been identified: purple C. tetracocca Zhang (PCTZ) and green C. tetracocca (GCTZ). This research was conducted to investigate the antioxidant activities and chemical compositions of different edible parts of PCTZ and GCTZ. Antioxidant activity was evaluated using DPPH, ABTS, HSA, and T-AOC assays, while the content of compounds was determined by HPLC. The findings demonstrated that the antioxidant capacity of PCTZ leaves is significantly superior to that of GCTZ leaves. Notably, theacrine, a rare compound, contains up to 2.075% in PCTZ leaves, indicating potential as a novel natural antidepressant and antioxidant. In conclusion, PCTZ is a distinctive tea beverage and a valuable genetic material for tea tree breeding due to its high theacrine and low caffeine characteristics.

Importance of Certain Varieties of Cucurbits in Enhancing Health: A Review

The Cucurbitaceae family is an extensive group of fruits and vegetables that exhibit common characteristics; for example, they are farmed on a global scale and exhibit a wide range of applications, including fresh consumption and use in various food and beverage products. As is frequent, many species or genera share a common name, and this can lead to some confusion when looking for information about a specific variety. In this review, we describe the findings about the biological activity, like antibacterial, antiviral, antidiabetic, and anticancer properties, of two genera of this family, Cucumis and Momordica, which have been characterized and evaluated in several research studies and regarding which information is readily accessible. Those activities rely on the various physicochemical qualities and nutritional content of each variety, including factors like β-carotene and polyphenols, among others. The goal of this review is to provide a rapid search for each activity examined in the literature, enabling future research on their potential uses in functional foods and nutraceutical supplements.

The Effect of Short-Term NAD3® Supplementation on Circulating Adult Stem Cells in Healthy Individuals Aged 40-70 Years

Objective This study aimed to assess the impact of acute and short-term supplementation with NAD3®, a theacrine-containing supplement, on circulating adult stem cell numbers in a healthy male and female population aged 40-70 years. Methods This was a double-blind, placebo-controlled crossover study with 12 participants randomized to receive either NAD3® or a placebo for seven days. Blood samples were collected after an overnight fast, before and after the seven-day supplementation period, and one and two hours after the final supplement dose. Using flow cytometry, circulating stem cells, including lymphocytoid CD34+ stem cells (CD45dimCD34+), stem cells associated with vascular maintenance and repair (CD45dimCD34+CD309+), CD34+ stem cells linked to a progenitor phenotype (CD45dimCD34+CD309neg), circulating endothelial stem cells (CD45negCD31+CD309+), and mesenchymal stem cells (CD45negCD90+) were quantified. Results Acute NAD3® supplementation did not result in the mobilization of stem cells from the bone marrow. However, seven days of daily NAD3® supplementation resulted in selective changes in circulating stem cell numbers. A significant time*treatment interaction was observed for CD45dimCD34+ cells (p=0.04) and CD45dimCD34+CD309neg cells (p=0.04), indicating a decrease in cell numbers with supplementation. There was also a trend toward an increase in circulating endothelial cells (p=0.08) with seven days of NAD3®supplementation. Conclusion Short-term NAD3® supplementation demonstrated an effect on the quantity of bone marrow-derived stem cells in circulation. The study suggests that this theacrine-containing supplement may play a role in modulating adult stem cell populations, emphasizing the potential impact of NAD3® on regenerative processes. Further research with extended supplementation periods and larger sample sizes is warranted to elucidate the functional consequences of these changes and explore the therapeutic implications for age-related declines in stem cell function.

Theacrine alleviates sepsis-induced acute kidney injury by repressing the activation of NLRP3/Caspase-1 inflammasome

Acute kidney injury (AKI) is a frequent and serious complication of sepsis, which results in a rapid decline of kidney function. Currently, there are no curative therapies for AKI. Theacrine is a purine alkaloid and exerts significant role in regulating inflammation, oxidative stress, and mood elevation. The study aims to evaluate the biological role and potential mechanism of theacrine in septic AKI. The murine and cellular models of septic AKI were established in lipopolysaccharide (LPS)-treated C57BL/6 mice and HK-2 cells, respectively. The effect of theacrine on alleviating septic AKI was assessed after pretreatment with theacrine in vivo and in vitro. We found that theacrine treatment significantly alleviated LPS-induced kidney injury, as evidenced by decreased levels of kidney injury markers (blood urea nitrogen and creatinine), inflammatory factors (IL-1β and IL-18), and cell apoptosis in vivo and in vitro. Mechanistically, theacrine markedly repressed the activation of NOD-like receptor (NLR) pyrin domain-containing protein 3 (NLRP3)inflammasome. As expected, MCC950 (a specific inhibitor of NLRP3) treatment also decreased LPS-induced production of IL-18 and IL-1β and cell apoptosis in HK-2 cells. More important, Nigericin sodiumsalt (a NLRP3 agonist) damaged the effect of theacrine on repressing kidney injury markers (blood urea nitrogen and creatinine), pro-inflammatory cytokines (IL-18 and IL-1β), and cell apoptosis. Taken together, these results demonstrate that theacrine alleviates septic AKI, at least in part by repressing the activation of NLRP3 inflammasome.

Ingredients with anti-inflammatory effect from medicine food homology plants

Inflammation occurs when the immune system responses to external harmful stimuli and infection. Chronic inflammation induces various diseases. A variety of foods are prescribed in the traditional medicines of many countries all over the world, which gave birth to the concept of medicine food homology. Over the past few decades, a number of secondary metabolites from medicine food homology plants have been demonstrated to have anti-inflammatory effects. In the present review, the effects and mechanisms of the medicine food homology plants-derived active components on relieving inflammation and inflammation-mediated diseases were summarized and discussed. The information provided in this review is valuable to future studies on anti-inflammatory ingredients derived from medicine food homology plants as drugs or food supplements.

Theacrine, a Potent Antidepressant Purine Alkaloid from a Special Chinese Tea, Promotes Adult Hippocampal Neurogenesis in Stressed Mice

Daily intake of tea has been known to relate to a low risk of depression. In this study, we report that a special variety of tea in China, Camellia assamica var. kucha (kucha), possesses antidepressant effects but with less adverse effects as compared to traditional tea Camellia sinensis. This action of kucha is related to its high amount of theacrine, a purine alkaloid structurally similar to caffeine. We investigated the antidepressant-like effects and mechanisms of theacrine in chronic water immersion restraint stress and chronic unpredictable mild stress mice models. PC12 cells and primary hippocampal neural stem cells were treated with stress hormone corticosterone (CORT) to reveal the potential antidepression mechanism of theacrine from the perspective of adult hippocampus neurogenesis. Results of behavioral and neurotransmitter analysis showed that intragastric administration of theacrine significantly counteracted chronic stress-induced depression-like disorders and abnormal 5-hydroxytryptamine (5-HT) metabolism with less central excitability. Further investigation from both in vivo and in vitro experiments indicated that the antidepressant mechanism of theacrine was associated with promoting adult hippocampal neurogenesis, via the modulation of the phosphodiesterase-4 (PDE4)/cyclic adenosine monophosphate (cAMP)/cAMP response-element binding (CREB)/brain-derived neurotrophic factor (BDNF)/tropomyosin-related kinase B (TrkB) pathway. Collectively, our findings could promote the prevalence of kucha as a common beverage with uses for health care and contribute to the development of theacrine as a potential novel antidepressant medicine.

Targeting Xanthine Oxidase by Natural Products as a Therapeutic Approach for Mental Disorders

Mental disorders comprise diverse human pathologies, including depression, bipolar affective disorder, schizophrenia, and dementia that affect millions of people around the world. The causes of mental disorders are unclear, but growing evidence suggests that oxidative stress and the purine/adenosine system play a key role in their development and progression. Xanthine oxidase (XO) is a flavoprotein enzyme essential for the catalysis of the oxidative hydroxylation of purines -hypoxanthine and xanthine- to generate uric acid. As a consequence of the oxidative reaction of XO, reactive oxygen species (ROS) such as superoxide and hydrogen peroxide are produced and, further, contribute to the pathogenesis of mental disorders. Altered XO activity has been associated with free radical-mediated neurotoxicity inducing cell damage and inflammation. Diverse studies reported a direct association between an increased activity of XO and diverse mental diseases including depression or schizophrenia. Small-molecule inhibitors, such as the well-known allopurinol, and dietary flavonoids, can modulate the XO activity and subsequent ROS production. In the present work, we review the available literature on XO inhibition by small molecules and their potential therapeutic application in mental disorders. In addition, we discuss the chemistry and molecular mechanism of XO inhibitors, as well as the use of structure-based and computational methods to design specific inhibitors with the capability of modulating XO activity.

Discovery of natural anti-inflammatory alkaloids: Potential leads for the drug discovery for the treatment of inflammation

Inflammation is an adaptive response of the immune system to tissue malfunction or homeostatic imbalance. Corticosteroids and non-steroidal anti-inflammatory drugs (NSAIDs) are frequently applied to treat varieties of inflammatory diseases but are associated with gastrointestinal, cardiovascular, and kidney side effects. Developing more effective and less toxic agents remain a challenge for pharmaceutical chemist due to the complexity of the different inflammatory processes. Alkaloids are widely distributed in plants with diverse anti-inflammatory activities, providing various potential lead compounds or candidates for the design and discovery of new anti-inflammatory drug candidates. Therefore, re-examining the anti-inflammatory alkaloid natural products is advisable, bringing more opportunities. In this review, we summarized and described the recent advances of natural alkaloids with anti-inflammatory activities and possible mechanisms in the period from 2009 to 2020. It is hoped that this review of anti-inflammatory alkaloids can provide new ideas for researchers engaged in the related fields and potential lead compounds for the discovery of anti-inflammatory drugs.

Theacrine From Camellia kucha and Its Health Beneficial Effects

Theacrine, i.e., 1,3,7,9-tetramethyluric acid, is one of the major purine alkaloids found in leaf of a wild tea plant species Camellia kucha Hung T. Chang. Theacrine has been attracted great attentions academically owing to its diverse health benefits. Present review examines the advances in the research on the health beneficial effects of theacrine, including antioxidant effect, anti-inflammatory effect, locomotor activation and reducing fatigue effects, improving cognitive effect, hypnotic effect, ameliorating lipid metabolism and inhibiting breast cancer cell metastasis effect. The inconsistent results in this research field and further expectations were also discussed.

A Theacrine-Based Supplement Increases Cellular NAD+ Levels and Affects Biomarkers Related to Sirtuin Activity in C2C12 Muscle Cells In Vitro

There is evidence in rodents to suggest that theacrine-based supplements modulate tissue sirtuin activity as well as other biological processes associated with aging. Herein, we examined if a theacrine-based supplement (termed NAD3) altered sirtuin activity in vitro while also affecting markers of mitochondrial biogenesis. The murine C2C12 myoblast cell line was used for experimentation. Following 7 days of differentiation, myotubes were treated with 0.45 mg/mL of NAD3 (containing ~2 mM theacrine) for 3 and 24 h (n = 6 treatment wells per time point). Relative to control (CTL)-treated cells, NAD3 treatments increased (p < 0.05) Sirt1 mRNA levels at 3 h, as well as global sirtuin activity at 3 and 24 h. Follow-up experiments comparing 24 h NAD3 or CTL treatments indicated that NAD3 increased nicotinamide phosphoribosyltransferase (NAMPT) and SIRT1 protein levels (p < 0.05). Cellular nicotinamide adenine dinucleotide (NAD⁺) levels were also elevated nearly two-fold after 24 h of NAD3 versus CTL treatments (p < 0.001). Markers of mitochondrial biogenesis were minimally affected. Although these data are limited to select biomarkers in vitro, these preliminary findings suggest that a theacrine-based supplement can modulate select biomarkers related to NAD⁺ biogenesis and sirtuin activity. However, these changes did not drive increases in mitochondrial biogenesis. While promising, these data are limited to a rodent cell line and human muscle biopsy studies are needed to validate and elucidate the significance of these findings.

Protective Effect of Saponins-Enriched Fraction of Gynostemma pentaphyllum against High Choline-Induced Vascular Endothelial Dysfunction and Hepatic Damage in Mice

Choline as a quaternary amine nutrient is metabolized to trimethylamine by gut microbiota and subsequently oxidized to circulating trimethylamine-N-oxide (TMAO), a gut-derived metabolite associated with liver toxicity and cardiovascular disease. The study was to probe the possible vasoprotective and hepatoprotective effects of total saponins of Gynostemma pentaphyllum (TSGP) in 3% high-choline water-feeding mice. The purified TSGP was obtained with content of 83.0% saponins, and its antioxidant activities were evaluated in vitro. Furthermore, the mice fed with high choline for 8 weeks significantly expressed vascular endothelial dysfunction and liver oxidative stress (p < 0.01 vs. Normal). Administration of TSGP at 400 and 800 mg/kg·body weight (b.w.) significantly lowered the serum total cholesterol (TC), triglyceride (TG), low density lipoprotein-cholesterol (LDL-C), endothelin-1 (ET-1) and thromboxane A₂ (TXA₂) levels, as well as hepatic malondialdehyde (MDA) formation, but effectively elevated the serum nitric oxide (NO), endothelial nitric oxide synthase (eNOS) and prostaglandin I₂ (PGI₂) levels, as well as alanine aminotransferase (ALT), aspartate aminotransferase (AST), T-superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities in high choline-fed mice. Hematoxylin-eosin (H&E) and oil red O staining also suggested that TSGP could exert the significant protection against endothelial dysfunction and liver injury in high choline-treated mice. These findings suggest that TSGP is of the saponins-enriched extract, and is a good candidate of dietary supplement and therapeutic application in vascular and hepatic oxidative injury.

Theacrine, a purine alkaloid from kucha, protects against Parkinson's disease through SIRT3 activation

BACKGROUND

Oxidative damage of dopaminergic neurons is the fundamental causes of Parkinson's disease (PD) that has no standard cure at present. Theacrine, a purine alkaloid from Chinese tea Kucha, has been speculated to benefit the neurodegeneration in PD, through similar actions to its chemical analogue caffeine, albeit excluding side effects. Theacrine has nowadays gained a lot of interest for its multiple benefits, while the investigations are weak and insufficient.

HYPOTHESIS/PURPOSE

It is well-known that tea has a wide range of functions, especially in the prevention and treatment of neurodegenerative diseases. Theacrine is an active monomer compound in Camellia assamica var. kucha Hung T. Chang & H.S.Wang (Kucha), which appears to be effective and safe in PD therapy. The aim of this study is to examine its actions in diverse PD models and explore the mechanisms.

STUDY DESIGN

For determination of theacrine's effects, we employed diverse oxidative damage-associated PD models, including 6-OHDA-treated rats, MPTP-treated mice/zebrafish and MPP⁺-treated SH-SY5Y cells, and using caffeine, selegiline and depranyl as positve control. For investigation and verification of the mechanisms, we utilized approaches testing mitochondrial function-related parameters and enzyme activity as well as applied gene knockdown and overexpression.

METHODS

We employed behavioral tests including spontaneous activity, pole, swimming, rotarod and gait, immunohistochemistry, HPLC, flow cytometry, immunohistochemistry, Western blot, gene knockdown by siRNA and overexpression by plasmid in this study.

RESULTS

Theacrine is demonstrated to retrieve the loss of dopaminergic neurons and the damages of behavioral performance in multiple animal models of PD (6-OHDA-treated rats and in MPTP-treated mice and zebrafish). The followed data of MPP⁺-treated SH-SY5Y cells indicate that theacrine relieves apoptosis resulted from oxidative damage and mitochondrial dysfunction. Further investigations illustrate that theacrine activates SIRT3 directly. It is of advantage to prevent apoptosis through SIRT3-mediated SOD2 deacetylation that reduces ROS accumulation and restores mitochondrial function. This concept is elaborated by 3TYP that inhibits SIRT3 enzyme activity and knockdown/overexpression of SIRT3 gene, demonstrating a crucial role of SIRT3 in theacrine-benefited dopaminergic neurons.

CONCLUSION

Theacrine prevents apoptosis of dopaminergic neurons through directly activating SIRT3 which deacetylating SOD2 and restoring mitochondrial functions.

Baiyacha, a wild tea plant naturally occurring high contents of theacrine and 3″-methyl-epigallocatechin gallate from Fujian, China

Baiyacha (BYC) is a kind of wild tea plant growing and utilizing in the remote mountain area of Fujian province, Southeastern China. However, scientific studies on this plant remain limited. Our results showed that BYC exhibits the typical morphological characteristics of Camellia gymnogyna Chang, a closely related species of C. sinensis (L.) O. Kuntze, which was not found in Fujian before. Chemical profiling revealed that parts of BYC plants are rich in purine alkaloids and catechins, especially featuring high levels of theacrine and 3″-methyl-epigallocatechin gallate (EGCG3″Me), chemical compounds with multiple biological activities that are rarely observed in regular tea plants. The contents of EGCG3″Me and theacrine in BYC both increased with the leaf maturity of tea shoots, whereas the caffeine content decreased significantly. The obtained results provide abundant information about the morphology and chemical compounds of BYC and may be used for tea production, breeding, and scientific research in the future.

Safety of Short-Term Supplementation with Methylliberine (Dynamine®) Alone and in Combination with TeaCrine® in Young Adults

Methylliberine (Dynamine^®; DYM) and theacrine (Teacrine^®; TCR) are purine alkaloids purported to have similar neuro-energetic effects as caffeine. There are no published human safety data on DYM, and research on TCR is limited. The purpose of this study was to examine the effect of four weeks of DYM supplementation with and without TCR on cardiovascular function and blood biomarkers. One-hundred twenty-five men and women (mean age 23.0 yrs, height 169.7 cm, body mass 72.1 kg; n = 25/group) were randomly assigned to one of five groups: low-dose DYM (100 mg), high-dose DYM (150 mg), low-dose DYM with TCR (100 mg + 50 mg), high-dose DYM with TCR (150 mg + 25 mg) , and placebo. Regardless of group and sex, significant main effects for time were noted for heart rate, systolic blood pressure, and QTc (p < 0.001), high-density lipoproteins (p = 0.002), mean corpuscular hemoglobin (p = 0.018), basophils (p = 0.006), absolute eosinophils (p = 0.010), creatinine (p = 0.004), estimated glomerular filtration rate (p = 0.037), chloride (p = 0.030), carbon dioxide (p = 0.023), bilirubin (p = 0.027), and alanine aminotransferase (p = 0.043), among others. While small changes were found in some cardiovascular and blood biomarkers, no clinically significant changes occurred. This suggests that DYM alone or in combination with TCR consumed at the dosages used in this study does not appear to negatively affect markers of health over four weeks of continuous use.

Theacrine alleviates chronic inflammation by enhancing TGF-β-mediated shifts via TGF-β/SMAD pathway in Freund's incomplete adjuvant-induced rats

Rheumatoid arthritis is a chronic and systemic autoimmune disease, which affects approximately 1% of the adult population worldwide. The present study investigated the therapeutic effect of theacrine (TC) on arthritis and its mechanisms in Freund's incomplete adjuvant (FIA)-induced SD rats. Rats were randomly divided into 5 groups: i) healthy control; ii) model; iii) positive control with methotrexate (MTX); iv) treatment with 12.5 mg/kg TC; and v) treatment with 25.0 mg/kg TC. The apparent scores, including changes in body weights, degree of paw swelling and arthritis indicators, were analyzed to evaluate the anti-chronic inflammatory effect of TC. The levels of interleukin (IL)-6 and transforming growth factor-β (TGF-β) in serum were measured by enzyme-linked immunosorbent assay. The protein and RNA expression levels of the critical factors in rats were measured to elucidate the mechanisms responsible for chronic inflammation and to verify molecular indexes of chronic inflammatory conditions. TC notably suppressed the severity of FIA-induced rat by attenuating the apparent scores, animal weight and inflammatory indexes in the 25 mg/kg TC group compared with the FIA rat model. Furthermore, TC significantly decreased the levels of IL-6 and increased the levels of TGF-β. Histopathological examinations indicated that TC rescued the synovial hyperplasia and inflammatory cell infiltration in joint tissues. In addition, TC enhanced TGF-β-mediated shifts in inflammatory marker expression in joint tissue. Overall, the present study demonstrated that TC exerted a superior anti-arthritic effect via the suppression of IL-6 and the activation of TGF-β by the TGF-β/SMAD pathway.

The effects of a caffeine-like supplement, TeaCrine®, on muscular strength, endurance and power performance in resistance-trained men

Background

TeaCrine® is the synthetic version to naturally occurring theacrine (1, 3, 7, 9-tetramethyluric acid) found in the leaves of Camellia kucha tea plants. A few studies have examined the effects of TeaCrine® on cognitive perception, but no research exists examining its effects on resistance exercise performance. The purpose of this study was to determine the efficacy of TeaCrine®, a caffeine-like compound, on maximal muscular strength, endurance, and power performance in resistance-trained men.

Methods

Twelve resistance-trained men participated in a randomized, double-blind, cross-over designed study. Each participant performed one-repetition maximum (1RM) bench press, 1RM squat, bench press repetitions to failure (RTF) at 70% 1RM, squat RTF at 70% 1RM, and 2-km rowing time trial 90 min after consumption of: (1) Caffeine 300 mg (CAFF300); (2) TeaCrine® 300 mg (TEA300); (3) TeaCrine® + Caffeine (COMBO; 150 mg/150 mg); (4) Placebo 300 mg (PLA). Power and velocity were measured using a TENDO Power Analyzer. Visual analogue scales for energy, focus, motivation to exercise, and fatigue were administered at baseline and 90 min post-treatment ingestion (pre-workout). Rating of perceived exertion was assessed after bench press RTF and squat RTF.

Results

There were no differences between groups for 1RM, RTF, and power in the bench press and squat exercises. Only CAFF300 resulted in significant increases in perceived energy and motivation to exercise vs. TEA300 and PLA (Energy: + 9.8%, 95% confidence interval [3.3–16.4%], p < 0.01; + 15.3%, 95% CI [2.2–28.5%], p < 0.02; Motivation to exercise: + 8.9%, 95% CI [0.2–17.6%], p = 0.04, + 14.8%, 95% CI [4.7–24.8%], p < 0.01, respectively) and increased focus (+ 9.6%, 95% CI [2.1–17.1%], p = 0.01) vs. TEA300, but there were no significant differences between CAFF300 and COMBO (Energy + 3.9% [− 6.9–14.7%], Focus + 2.5% [− 6.3–11.3%], Motivation to exercise + 0.5% [− 11.6–12.6%]; p > 0.05).

Conclusion

Neither TEA300, CAFF300, COMBO, or PLA (when consumed 90 min pre-exercise) improved muscular strength, power, or endurance performance in resistance-trained men. Only CAFF300 improved measures of focus, energy, and motivation to exercise.

Theacrine attenuates epithelial mesenchymal transition in human breast cancer MDA-MB-231 cells

Theacrine, a purine alkaloid structurally similar to caffeine, has recently become of interest as a potential therapeutic compound. Here, we investigated the antimetastatic potential of theacrine on human breast cancer MDA-MB-231 cells. We observed that theacrine can reverse epithelial-to-mesenchymal transition (EMT), which resulted in a decrease in the levels of mesenchymal markers (Fibronectin, Vimentin, N-cadherin, Twist, and Snail) and an increase in the levels of epithelial markers (Occludin and E-cadherin) in the cells. Additionally, theacrine attenuates TGF-β-induced EMT, cell adhesion, migration, and invasion in MDA-MB-231 cells. Overall, our results suggest that theacrine may inhibit the breast cancer cell metastasis by reversing the EMT process.

Theacrine protects against nonalcoholic fatty liver disease by regulating acylcarnitine metabolism

OBJECTIVE

Acylcarnitine metabolism disorder contributes significantly to the pathogenesis of nonalcoholic fatty liver disease (NAFLD). There are, however, few ideal medications for NAFLD, which work by targeting acylcarnitine metabolism. The aim of this study was to investigate the protective effects of theacrine, a rare purine alkaloid isolated from Camellia assamica var. kucha, against acylcarnitine metabolism disorder in NAFLD.

METHODS

The pharmacological activities of theacrine were studied using high-fat diet (HFD)-fed ApoE-/- and C57BL/6J mice models. Oleate-treated HepG2 and L-02 cells were used to investigate the molecular mechanism of theacrine on acylcarnitine metabolism. The target of theacrine was confirmed in vitro as the blockade of sirtuin 3 (SIRT3) and protein kinase A.

RESULTS

Theacrine inhibits hepatic steatosis and liver inflammation and improves energy expenditure in HFD-fed mice. Theacrine ameliorates acylcarnitine metabolism disorder in HFD-fed mice and oleate-treated hepatocytes by improving fatty acid oxidation. The underlying mechanism involves theacrine's activation of the mitochondrial deacetylase SIRT3 and consequently, the increased activity of long-chain acyl coenzyme A dehydrogenase (LCAD) through deacetylation.

CONCLUSION

Theacrine promotes acylcarnitine metabolism in NAFLD through the SIRT3/LCAD signaling pathway. The target of theacrine's activities on NAFLD is identified as SIRT3.

Assessment of the Drug-Drug Interaction Potential Between Theacrine and Caffeine in Humans

Objective: Theacrine, a methylurate class purine alkaloid, triggers diverse pharmacologic responses, including psychostimulatory activity by modulation of adenosinergic and dopaminergic pathways. In a double-blind, placebo-controlled study, theacrine increased energy, concentration, and mood, while reducing fatigue. Because caffeine, a methylxanthine purine alkaloid, is frequently coadministered with theacrine, we sought to determine if a pharmacokinetic and/or pharmacodynamic interaction existed between theacrine and caffeine. Methods: Eight healthy adults received theacrine, as TeaCrine^® (25 or 125 mg), caffeine (150 mg), or a combination of theacrine (125 mg) and caffeine (150 mg) in a randomized, double-blind crossover study. Blood samples were collected over a 24-hour period and analyzed by Liquid chromatrography-mass spectrometry/mass spectrometry (LC-MS/MS) for theacrine, caffeine, and paraxanthine. Pharmacodynamic response markers, heart rate and blood pressure, were recorded. Results: Theacrine pharmacokinetics was similar following administration of theacrine alone. Caffeine coadministration increased maximum plasma concentration and area under the curve of theacrine without altering theacrine half-life. Theacrine had no impact on caffeine or paraxanthine pharmacokinetics. There was no difference between treatment groups with regard to heart rate or systolic/diastolic blood pressure. Conclusions: Coadministration of theacrine and caffeine results in a clinically significant pharmacokinetic interaction, viz., increased theacrine exposure. Enhanced oral bioavailability is the most likely mechanism by which caffeine alters theacrine exposure. However, further studies examining the contribution of presystemic elimination mechanisms, for example, efflux transport and/or gut metabolism, to theacrine bioavailability are needed to confirm the exact mechanism(s). Hemodynamic parameters were unaltered despite the pharmacokinetic interaction, suggesting that coadministration of caffeine and theacrine is safe at the doses administered.

Theacrine: A purine alkaloid from Camellia assamica var. kucha with a hypnotic property via the adenosine system

Theacrine (l,3,7,9-tetramethyluric acid), a purine alkaloid from Camellia assamica var. kucha, has diverse pharmacological properties, including sedative and hypnotic activities, anti-inflammatory and analgesic activities, antidepressant effects, and a protective effect against stress-provoked liver damage. The present study aims to investigate the possible mechanism of the hypnotic activity of theacrine. The results revealed that theacrine significantly enhanced pentobarbital-induced sleep at a dose of 3.0mg/kg (i.g.) in mice. Sleep parameter analysis by EEG and EMG showed that theacrine obviously shortened wake time and increased NREM sleep time and that theacrine almost had no effect on REM sleep. Meanwhile, theacrine markedly attenuated caffeine (a nonselective antagonist of adenosine receptor)-induced insomnia. In pretreatment with the adenosine A₁ receptor antagonist DPCPX and the A_2A receptor antagonist SCH 58261, theacrine significantly reversed the decrease in sleeping time in pentobarbital-treated mice. In addition, theacrine also markedly increased the adenosine content in the hippocampus of rats. These results suggested that theacrine might mediate the adenosine system to augment pentobarbital-induced sleep.

Protective effect of Momordica charantia water extract against liver injury in restraint-stressed mice and the underlying mechanism

Background: Momordica charantia is used in China for its jianghuo (heat-clearing and detoxifying) effects. The concept of shanghuo (the antonym of jianghuo, excessive internal heat) in traditional Chinese medicine is considered a type of stress response of the body. The stress process involves internal organs, especially the liver. Objective: We hypothesized that Momordica charantia water extract (MWE) has a hepatoprotective effect and can protect the body from stress. The aim of this study was to investigate the possible effects of MWE against liver injury in restraint-stressed mice. Design: The mice were intragastrically administered with MWE (250, 500 and 750 mg/kg bw) daily for 7 days. The Normal Control (NC) and Model groups were administered distilled water. A positive control group was intragastrically administered vitamin C 250 mg/kg bw. After the last administration, mice were restrained for 20 h. Results: MWE reduced the serum AST and ALT, reduced the NO content and the protein expression level of iNOSin the liver; significantly reduced the mitochondrial ROS content, increased the mitochondrial membrane potential and the activities of mitochondrial respiratory chain complexes I and II in restraint-stressed mice. Conclusions: The results indicate that MWE has a protective effect against liver injury in restraint-stressed mice. Abbreviations: MWE: Momordica charantia water extract; M. charantia: Momordica charantia L.; ROS: reactive oxygen species; NO: nitric oxide; iNOS: inducible nitric oxide synthase; IL-1β: interleukin-1 beta; TNF-α: tumor necrosis factor alpha; IL-6: interleukin 6; IFN-γ: interferon gamma; VC: vitamin C; ALT: alanine transaminase; AST: aspartate aminotransferase; GSH: glutathione; GSH-PX: glutathione peroxidase; MDA: malondialdehyde; BCA: bicinchoninic acid; TBARS: thiobarbituric acid reactive substances; Trolox: 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid; JC-B: Janus Green B; DW: dry weight; FC: Folin-Ciocalteu; GAE: gallic acid equivalents; bw: body weight; NC: normal control group; Model: restraint stress model group; VC: positive control vitamin C group, 250 mg/kg bw; MWEL: Momordica charantia water extract low-dose group, 250 mg/kg bw; MWEM: Momordica charantia water extract middle-dose group, 500 mg/kg bw; MWEH: Momordica charantia water extract high-dose group, 750 mg/kg bw; HE: hematoxylin and eosin; ORAC: total oxygen radical absorbance capacity; ABAP: dihydrochloride; ATP: adenosine triphosphate.

Phenolic-rich lychee (Litchi chinensis Sonn.) pulp extracts offer hepatoprotection against restraint stress-induced liver injury in mice by modulating mitochondrial dysfunction

The pulp from lychee, a tropical to subtropical fruit, contains large quantities of phenolic compounds and exhibits antioxidant activities both in vitro and in vivo. In the present study, we investigated the mechanisms underlying the hepatoprotective effects of lychee pulp phenolics (LPPs) against restraint stress-induced liver injury in mice. After 18 h of restraint stress, increased levels of serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities were observed. High levels of thiobarbituric acid reactive substances (TBARS) were also found. Restraint stress causes liver damage, which was protected against by LPP pretreatment at a dosage of 200 mg (kg d)(-1) for 21 consecutive days. This treatment remarkably decreased the serum ALT, AST and TBARS levels, elevated the liver glutathione (GSH) content, and the activities of glutathione peroxidase (GPx), superoxide dismutase (SOD) and catalase (CAT). Furthermore, respiratory chain complex and Na(+)-K(+)-ATPase activities were enhanced in liver mitochondria, while mitochondrial membrane potential levels and reactive oxygen species (ROS) production decreased. Thus, treatment with LPPs ameliorated restraint stress-induced liver mitochondrial dysfunction. These results suggest that LPPs protect the liver against restraint stress-induced damage by scavenging free radicals and modulating mitochondrial dysfunction. Thus, lychee pulp may be a functional biofactor to mitigate oxidative stress.

A 90-Day Oral Toxicological Evaluation of the Methylurate Purine Alkaloid Theacrine

A 90-day repeated-dose oral toxicological evaluation was conducted according to GLP and OECD guidelines on the methylurate purine alkaloid theacrine, which is found naturally in certain plants. Four groups of Hsd.Brl.Han Wistar rats (ten/sex/group) were administered theacrine by gavage doses of 0 (vehicle only), 180, 300, and 375 mg/kg bw/day. Two females and one male in the 300 and 375 mg/kg bw/day groups, respectively, died during the study. Histological examination revealed centrilobular hepatocellular necrosis as the probable cause of death. In 375 mg/kg bw/day males, slight reductions in body weight development, food consumption, and feed efficiency, decreased weight of the testes and epididymides and decreased intensity of spermatogenesis in the testes, lack or decreased amount of mature spermatozoa in the epididymides, and decreased amount of prostatic secretions were detected at the end of the three months. At 300 mg/kg bw/day, slight decreases in the weights of the testes and epididymides, along with decreased intensity of spermatogenesis in the testes, and lack or decreased amount of mature spermatozoa in the epididymides were detected in male animals. The NOAEL was considered to be 180 mg/kg bw/day, as at this dose there were no toxicologically relevant treatment-related findings in male or female animals.

Lycibarbarspermidines A-O, New Dicaffeoylspermidine Derivatives from Wolfberry, with Activities against Alzheimer's Disease and Oxidation

Fifteen new dicaffeoylspermidine derivatives, lycibarbarspermidines A-O (1-15), were isolated from the fruit of Lycium barbarum (wolfberry). The structures were unambiguously determined by spectroscopic analyses and chemical methods. Dicaffeoylspermidine derivatives, a rare kind of plant secondary metabolites, are primarily distributed in the family of Solanaceae. Only six compounds were structurally identified, and all of them are acyclic aglycones. Compounds 1-15 are the first glycosidic products of dicaffeoylspermidine derivatives, and compounds 14-15 are the first cyclization products of dicaffeoylspermidine derivatives. Moreover, dicaffeoylspermidine derivatives were first isolated and identified from wolfberry. The short-term memory assay on a transgenic fly Alzheimer's disease (AD) model showed that 1-15 exhibited different levels of anti-AD activity. The oxygen radical absorbance capacity assay revealed that 1-15 all displayed antioxidant capacity. Both anti-AD and antioxidant functions are related to the effects of wolfberry. Therefore, dicaffeoylspermidine derivatives are considered beneficial constituents responsible for the antiaging, neuroprotective, anti-AD, and antioxidant effects of wolfberry.

Cognitive Performance and Mood Following Ingestion of a Theacrine-Containing Dietary Supplement, Caffeine, or Placebo by Young Men and Women

Theacrine is a purine alkaloid found primarily in the leaves of the Camellia Kucha plant and is now included within dietary supplements. To compare the effects of a theacrine-containing dietary supplement with caffeine and placebo on energy and mood, as well as objective measures of cognitive performance, heart rate, and blood pressure, 10 healthy men (20.8 ± 0.7 years) and 10 healthy women (22.2 ± 1.1 years) ingested the dietary supplement TheaTrim (Purus Labs; containing a branded form of theacrine (Teacrine™) and caffeine (150 mg)), caffeine only (150 mg), or a placebo on three different days, separated by approximately one week. Before, and for up to 4 h following, ingestion of the assigned condition, subjects completed a subjective assessment of energy and mood, as well as tests of cognitive performance (trail making test (TMT), digit symbol substitution test (DSST)), and reaction time. Heart rate and blood pressure were measured. No condition or interaction effects were noted for TMT, DSST, or reaction time, despite a trend for improvement in selected variables with both TheaTrim and caffeine treatment. Condition effects or trends were noted for subjective feelings, with values for attentive, alert, focused, and energetic higher for TheaTrim than for placebo and caffeine, while values for lethargic and groggy were lower for TheaTrim than for placebo and caffeine. Heart rate and blood pressure were largely unaffected by treatment. These data indicate that TheaTrim treatment does not result in a statistically significant improvement in cognitive performance but may favorably impact multiple subjective feelings related to energy and mood.

Determining antioxidant activities of lactobacilli cell-free supernatants by cellular antioxidant assay: a comparison with traditional methods

Antioxidant activity of lactic acid bacteria is associated with multiple health-protective effects. Traditional indexes of chemical antioxidant activities poorly reflect the antioxidant effects of these bacteria in vivo. Cellular antioxidant activity (CAA) assay was used in this study to determine the antioxidant activity of cell-free supernatants (CFSs) of 10 Lactobacillus strains. The performance of the CAA assay was compared with that of four chemical antioxidant activity assays, namely, DPPH radical scavenging, hydroxyl radical scavenging (HRS), reducing power (RP), and inhibition of linoleic acid peroxidation (ILAP). Results of the CAA assay were associated with those of DPPH and ILAP assays, but not with those of RP and HRS assays. The inter- and intra-specific antioxidant activities of CFS were characterized by chemical and CAA assays. L. rhamnosus CCFM 1107 displayed a high antioxidative effect similar to positive control L. rhamnosus GG ATCC 53103 in all of the assays. The CAA assay is a potential method for the detection of antioxidant activities of lactobacilli CFSs.

Phloridzin improves lipoprotein lipase activity in stress-loaded mice via AMPK phosphorylation

Long-term stress exposure can lead to disturbed homeostasis and cause many life-style diseases. Phloridzin possesses various bioactivities, but the understanding of the effects of phloridzin on stress-related lipid metabolism disorder is limited. Our results demonstrate that phloridzin improved plasma lipoprotein lipase (LPL) activity and triglyceride metabolism in restrained mice. A decrease of angiopoietin-like protein 4 (ANGPTL4) mRNA expression and an increase of AMP-activated protein kinase (AMPK) phosphorylation were observed after phloridzin treatment. After inhibiting AMPK phosphorylation, the effects of phloridzin on the amelioration of plasma LPL activity and suppression of ANGPTL4 expression were blocked. In addition, cardiac AMPK phosphorylation, plasma LPL activity and ANGPTL4 expression were also affected by phloridzin, even if the glucocorticoid receptor was blocked. Taken together, the down-regulation of ANGPTL4 expression by phloridzin was probably via a direct activation of AMPK pathway. This discovery can provide a biochemical and nutritional basis for the use of phloridzin-containing food and beverage in daily life.