1.A Key Metabolic Regulator of Bone and Cartilage Health
Elizabeth PÉREZ-HERNÁNDEZ ; Jesús Javier PASTRANA-CARBALLO ; Fernando GÓMEZ-CHÁVEZ ; Ramesh C. GUPTA ; Nury PÉREZ-HERNÁNDEZ
Endocrinology and Metabolism 2022;37(4):559-574
Taurine, a cysteine-derived zwitterionic sulfonic acid, is a common ingredient in energy drinks and is naturally found in fish and other seafood. In humans, taurine is produced mainly in the liver, and it can also be obtained from food. In target tissues, such as the retina, heart, and skeletal muscle, it functions as an essential antioxidant, osmolyte, and antiapoptotic agent. Taurine is also involved in energy metabolism and calcium homeostasis. Taurine plays a considerable role in bone growth and development, and high-profile reports have demonstrated the importance of its metabolism for bone health. However, these reports have not been collated for more than 10 years. Therefore, this review focuses on taurine–bone interactions and covers recently discovered aspects of taurine’s effects on osteoblastogenesis, osteoclastogenesis, bone structure, and bone pathologies (e.g., osteoporosis and fracture healing), with due attention to the taurine–cartilage relationship.
2.Toxic potential of palytoxin.
Jiří PATOCKA ; Ramesh C GUPTA ; Qing-hua WU ; Kamil KUCA
Journal of Huazhong University of Science and Technology (Medical Sciences) 2015;35(5):773-780
This review briefly describes the origin, chemistry, molecular mechanism of action, pharmacology, toxicology, and ecotoxicology of palytoxin and its analogues. Palytoxin and its analogues are produced by marine dinoflagellates. Palytoxin is also produced by Zoanthids (i.e. Palythoa), and Cyanobacteria (Trichodesmium). Palytoxin is a very large, non-proteinaceous molecule with a complex chemical structure having both lipophilic and hydrophilic moieties. Palytoxin is one of the most potent marine toxins with an LD50 of 150 ng/kg body weight in mice exposed intravenously. Pharmacological and electrophysiological studies have demonstrated that palytoxin acts as a hemolysin and alters the function of excitable cells through multiple mechanisms of action. Palytoxin selectively binds to Na(+)/K(+)-ATPase with a Kd of 20 pM and transforms the pump into a channel permeable to monovalent cations with a single-channel conductance of 10 pS. This mechanism of action could have multiple effects on cells. Evaluation of palytoxin toxicity using various animal models revealed that palytoxin is an extremely potent neurotoxin following an intravenous, intraperitoneal, intramuscular, subcutaneous or intratracheal route of exposure. Palytoxin also causes non-lethal, yet serious toxic effects following dermal or ocular exposure. Most incidents of palytoxin poisoning have manifested after oral intake of contaminated seafood. Poisonings in humans have also been noted after inhalation, cutaneous/systemic exposures with direct contact of aerosolized seawater during Ostreopsis blooms and/or through maintaining aquaria containing Cnidarian zoanthids. Palytoxin has a strong potential for toxicity in humans and animals, and currently this toxin is of great concern worldwide.
Acrylamides
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chemistry
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isolation & purification
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toxicity
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Animals
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Anthozoa
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pathogenicity
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physiology
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Dinoflagellida
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pathogenicity
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physiology
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Dogs
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Guinea Pigs
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Haplorhini
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Humans
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Lethal Dose 50
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Marine Toxins
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chemistry
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isolation & purification
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toxicity
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Mice
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Rabbits
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Rats
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Seaweed
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pathogenicity
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physiology
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Shellfish Poisoning
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physiopathology
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Sodium-Potassium-Exchanging ATPase
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metabolism
3.Small interfering RNA for cancer treatment: overcoming hurdles in delivery.
Nitin Bharat CHARBE ; Nikhil D AMNERKAR ; B RAMESH ; Murtaza M TAMBUWALA ; Hamid A BAKSHI ; Alaa A A ALJABALI ; Saurabh C KHADSE ; Rajendran SATHEESHKUMAR ; Saurabh SATIJA ; Meenu METHA ; Dinesh Kumar CHELLAPPAN ; Garima SHRIVASTAVA ; Gaurav GUPTA ; Poonam NEGI ; Kamal DUA ; Flavia C ZACCONI
Acta Pharmaceutica Sinica B 2020;10(11):2075-2109
In many ways, cancer cells are different from healthy cells. A lot of tactical nano-based drug delivery systems are based on the difference between cancer and healthy cells. Currently, nanotechnology-based delivery systems are the most promising tool to deliver DNA-based products to cancer cells. This review aims to highlight the latest development in the lipids and polymeric nanocarrier for siRNA delivery to the cancer cells. It also provides the necessary information about siRNA development and its mechanism of action. Overall, this review gives us a clear picture of lipid and polymer-based drug delivery systems, which in the future could form the base to translate the basic siRNA biology into siRNA-based cancer therapies.