Osteoporosis, characterized by loss of bone mass and microarchitectural deterioration of bone tissue, results in enhanced bone fragility and increases risk of fractureIll. In China, the incidence of primary osteoporos...Osteoporosis, characterized by loss of bone mass and microarchitectural deterioration of bone tissue, results in enhanced bone fragility and increases risk of fractureIll. In China, the incidence of primary osteoporosis is as high as 50%-70% in 60-69 years old females and approximately 30% in 60-69 years old males[21, which is closely related with the low intake of calcium. According to the nationwide nutrition and health survey in 2002 in China, the average daily calcium intake of Chinese residents is 391 mg, accounting for 41% of the recommended calcium intake.展开更多
Mitochondrial calcium uniporter(MCU)is a conserved calcium ion(Ca^(2+))transporter in the mitochondrial inner membrane of eukaryotic cells.How MCU proteins regulate Ca^(2+)flow and modulate plant cell development rema...Mitochondrial calcium uniporter(MCU)is a conserved calcium ion(Ca^(2+))transporter in the mitochondrial inner membrane of eukaryotic cells.How MCU proteins regulate Ca^(2+)flow and modulate plant cell development remain largely unclear.Here,we identified the gene GhMCU4 encoding a MCU protein that negatively regulates plant development and fiber elongation in cotton(Gossypium hirsutum).GhMCU4expressed constitutively in various tissues with the higher transcripts in elongating fiber cells.Knockdown of GhMCU4 in cotton significantly elevated the plant height and root length.The calcium signaling pathway was significantly activated and calcium sensor genes,including Ca^(2+)dependent modulator of interactor of constitutively active ROP(GhCMI1),calmodulin like protein(GhCML46),calciumdependent protein kinases(GhCPKs),calcineurin B-like protein(GhCBLs),and CBL-interacting protein kinases(GhCIPKs),were dramatically upregulated in GhMCU4-silenced plants.Metabolic processes were preferentially enriched,and genes related to regulation of transcription were upregulated in GhMCU4-silenced plants.The contents of Ca^(2+)and H_(2)O_(2)were significantly increased in roots and leaves of GhMCU4-silenced plants.Fiber length and Ca^(2+)and H_(2)O_(2)contents in fibers were significantly increased in GhMCU4-silenced plants.This study indicated that GhMCU4 plays a negative role in regulating cell elongation in cotton,thus expanding understanding in the role of MCU proteins in plant growth and development.展开更多
Effects of refined konjac meal (RKM) on the calcium and phosphorus metabolism and bone parameters were observed in rats of both sexes fed with food containing 1% of RKM for 18 months. A comparable group of rats fed on...Effects of refined konjac meal (RKM) on the calcium and phosphorus metabolism and bone parameters were observed in rats of both sexes fed with food containing 1% of RKM for 18 months. A comparable group of rats fed on basic diet only was used as a control.Results obtained indicate that all the measured parameters (serum calcium and phosphorus level, femur weight and its calcium and phesphorus content, and the osteometry of the tibia) showed no significant difference between the experimental and the control groups.Thus there is no adverse effect either on the calcium and phosphorus metabolism or on the bone after a long-term intake at a moderate dosage.展开更多
This experiment was conducted to investigate the effect of dietary calcium(Ca)or phosphorus(P)deficiency on bone development and related Ca or P metabolic utilization parameters of broilers from 22 to 42 days of age b...This experiment was conducted to investigate the effect of dietary calcium(Ca)or phosphorus(P)deficiency on bone development and related Ca or P metabolic utilization parameters of broilers from 22 to 42 days of age based on our previous study,which indicated that dietary Ca or P deficiency impaired the bone development by regulating related Ca or P metabolic utilization parameters of broilers from 1 to 21 days of age.A total of 504 one-day-old Arbor Acres male broilers were randomly assigned to 1 of 4 treatments with 7 replicates in a completely randomized design,and fed the normal control and Ca-or P-deficient diets from 1 to 21 days of age.At 22 days of age,the broilers were further fed the normal control diet(0.90%Ca+0.35%non-phytate P(NPP)),the P-deficient diet(0.90%Ca+0.18%NPP),the Ca-deficient diet(0.30%Ca+0.35%NPP)or the Ca and P-deficient diet(0.30%Ca+0.18%NPP),respectively.The results showed that dietary Ca or P deficiency decreased(P<0.05)tibia bone mineral density(BMD),bone breaking strength(BBS),ash content,tibia ash Ca content and serum P content on days 28 and 42,but increased(P<0.05)tibia alkaline phosphatase(ALP)activity of broilers on day 42 compared with the control group.Furthermore,the broilers fed the P-deficient diet had the lowest(P<0.05)tibia BMD,BBS,ash content,serum P content and the highest(P<0.05)serum Ca content on day 28 compared with those fed the Ca-deficient or Ca and P-deficient diets.The results from the present study indicated that the bone development and related Ca or P metabolic utilization parameters of broilers were the most sensitive to dietary P deficiency,followed by dietary Ca deficiency or Ca and P-deficiency;dietary Ca or P deficiency impaired the bone development possibly by regulating serum Ca and P contents as well as tibia Ca content and ALP activity of broilers from 22 to 42 days of age.展开更多
The plasma membrane Ca2+-ATPase(PMCA)is an ATPdriven pump that is critical for the maintenance of low resting[Ca2+]i in all eukaryotic cells.Metabolic stress, either due to inhibition of mitochondrial or glycolytic me...The plasma membrane Ca2+-ATPase(PMCA)is an ATPdriven pump that is critical for the maintenance of low resting[Ca2+]i in all eukaryotic cells.Metabolic stress, either due to inhibition of mitochondrial or glycolytic metabolism,has the capacity to cause ATP depletion and thus inhibit PMCA activity.This has potentially fatal consequences,particularly for non-excitable cells in which the PMCA is the major Ca2+efflux pathway.This is because inhibition of the PMCA inevitably leads to cytosolic Ca2+ overload and the consequent cell death.However,the relationship between metabolic stress,ATP depletion and inhibition of the PMCA is not as simple as one would have originally predicted.There is increasing evidence that metabolic stress can lead to the inhibition of PMCA activity independent of ATP or prior to substantial ATP depletion.In particular,there is evidence that the PMCA has its own glycolytic ATP supply that can fuel the PMCA in the face of impaired mitochondrial function.Moreover, membrane phospholipids,mitochondrial membrane potential,caspase/calpain cleavage and oxidative stress have all been implicated in metabolic stress-induced inhibition of the PMCA.The major focus of this review is to challenge the conventional view of ATP-dependent regulation of the PMCA and bring together some of the alternative or additional mechanisms by which metabolic stress impairs PMCA activity resulting in cytosolic Ca2+ overload and cytotoxicity.展开更多
Objective: It remains unknown whether calcium metabolism has any effect on the clinical presentation of superior semicircular canal dehiscence(SSCD). Our aim was to analyse the adjusted calcium and vitamin D levels in...Objective: It remains unknown whether calcium metabolism has any effect on the clinical presentation of superior semicircular canal dehiscence(SSCD). Our aim was to analyse the adjusted calcium and vitamin D levels in SSCD patients compared to a control group.Methods: This was a prospective case-control study performed in a tertiary referral center, university teaching hospital in the UK. It included all new patients with SSCD seen in a dedicated skull base clinic over a 5-year period(2015-2019) compared to a gender and age matched control group. The main outcome of the study was adjusted calcium and Vitamin D levels between the two groups.Results: A total of 31 SSCD patients were recruited with a matched number of control patients. The mean Vitamin D level on the SSCD group was 44.8 nmoL/l(SD: 20.8) compared to 47.5 nmoL/l(SD: 27.4) on the control group(p = 0.702). Mean Adjusted calcium level was 2.34 mmoL/l(SD: 0.7) for SSCD compared to2.41 mmoL/l(SD: 0.11) for controls(p = 0.01), being within normal limits for both the SSCD and the control group.Conclusion: Our study did not identify a link between Vitamin D levels and presence of SSCD. Normal adjusted calcium values were found in both groups. Despite that a statistically significant lower calcium level was found in the SSCD group which could indicate that suboptimal levels of calcium may affect the micro-environment of the otic capsule at the SSC region.展开更多
The extensive use of nanoparticles(NPs)in diverse applications causes their localization to aquatic habitats,affecting the metabolic products of primary producers in aquatic ecosystems,such as algae.Synthesized calciu...The extensive use of nanoparticles(NPs)in diverse applications causes their localization to aquatic habitats,affecting the metabolic products of primary producers in aquatic ecosystems,such as algae.Synthesized calcium oxide nanoparticles(CaO NPs)are of the scarcely studied NPs.Thus,the current work proposed that the exposure to CaO NPs may instigate metabolic pathway to be higher than that of normally growing algae,and positively stimulate algal biomass.In this respect,this research was undertaken to study the exposure effect of CaO NPs(0,20,40,60,80,and 100μg mL^(−1))on the growth,photosynthesis,respiration,oxidative stress,antioxidants,and lipid production of the microalga Coccomyxa chodatii SAG 216-2.The results showed that the algal growth concomitant with chlorophyll content,photosynthesis,and calcium content increased in response to CaO NPs.The contents of biomolecules such as proteins,amino acids,and carbohydrates were also promoted by CaO NPs with variant degrees.Furthermore,lipid production was enhanced by the applied nanoparticles.CaO NPs induced the accumulation of hydrogen peroxide,while lipid peroxidation was reduced,revealing no oxidative behavior of the applied nanoparticles on alga.Also,CaO NPs have a triggering effect on the antioxidant enzymes such as superoxide dismutase,catalase,ascorbate peroxidase,and guaiacol peroxidase.The results recommended the importance of the level of 60μg mL^(−1) CaO NPs on lipid production(with increasing percentage of 65%compared to control)and the highest dry matter acquisition of C.chodatii.This study recommended the feasibility of an integrated treatment strategy of CaO NPs in augmenting biomass,metabolic up-regulations,and lipid accumulation in C.chodatii.展开更多
Mitochondria play an essential role in neural function,such as supporting normal energy metabolism,regulating reactive oxygen species,buffering physiological calcium loads,and maintaining the balance of morphology,sub...Mitochondria play an essential role in neural function,such as supporting normal energy metabolism,regulating reactive oxygen species,buffering physiological calcium loads,and maintaining the balance of morphology,subcellular distribution,and overall health through mitochondrial dynamics.Given the recent technological advances in the assessment of mitochondrial structure and functions,mitochondrial dysfunction has been regarded as the early and key pathophysiological mechanism of cognitive disorders such as Alzheimer’s disease,Parkinson’s disease,Huntington’s disease,mild cognitive impairment,and postoperative cognitive dysfunction.This review will focus on the recent advances in mitochondrial medicine and research methodology in the field of cognitive sciences,from the perspectives of energy metabolism,oxidative stress,calcium homeostasis,and mitochondrial dynamics(including fission-fusion,transport,and mitophagy).展开更多
文摘Osteoporosis, characterized by loss of bone mass and microarchitectural deterioration of bone tissue, results in enhanced bone fragility and increases risk of fractureIll. In China, the incidence of primary osteoporosis is as high as 50%-70% in 60-69 years old females and approximately 30% in 60-69 years old males[21, which is closely related with the low intake of calcium. According to the nationwide nutrition and health survey in 2002 in China, the average daily calcium intake of Chinese residents is 391 mg, accounting for 41% of the recommended calcium intake.
基金supported by National Key Research and Development Program of China(2022YFD1200300)Jiangsu Key R&D Program(BE2022384)the Collaborative Innovation Center for Modern Crop Production co-sponsored by Province and Ministry(CIC-MCP)(No.10)。
文摘Mitochondrial calcium uniporter(MCU)is a conserved calcium ion(Ca^(2+))transporter in the mitochondrial inner membrane of eukaryotic cells.How MCU proteins regulate Ca^(2+)flow and modulate plant cell development remain largely unclear.Here,we identified the gene GhMCU4 encoding a MCU protein that negatively regulates plant development and fiber elongation in cotton(Gossypium hirsutum).GhMCU4expressed constitutively in various tissues with the higher transcripts in elongating fiber cells.Knockdown of GhMCU4 in cotton significantly elevated the plant height and root length.The calcium signaling pathway was significantly activated and calcium sensor genes,including Ca^(2+)dependent modulator of interactor of constitutively active ROP(GhCMI1),calmodulin like protein(GhCML46),calciumdependent protein kinases(GhCPKs),calcineurin B-like protein(GhCBLs),and CBL-interacting protein kinases(GhCIPKs),were dramatically upregulated in GhMCU4-silenced plants.Metabolic processes were preferentially enriched,and genes related to regulation of transcription were upregulated in GhMCU4-silenced plants.The contents of Ca^(2+)and H_(2)O_(2)were significantly increased in roots and leaves of GhMCU4-silenced plants.Fiber length and Ca^(2+)and H_(2)O_(2)contents in fibers were significantly increased in GhMCU4-silenced plants.This study indicated that GhMCU4 plays a negative role in regulating cell elongation in cotton,thus expanding understanding in the role of MCU proteins in plant growth and development.
文摘Effects of refined konjac meal (RKM) on the calcium and phosphorus metabolism and bone parameters were observed in rats of both sexes fed with food containing 1% of RKM for 18 months. A comparable group of rats fed on basic diet only was used as a control.Results obtained indicate that all the measured parameters (serum calcium and phosphorus level, femur weight and its calcium and phesphorus content, and the osteometry of the tibia) showed no significant difference between the experimental and the control groups.Thus there is no adverse effect either on the calcium and phosphorus metabolism or on the bone after a long-term intake at a moderate dosage.
基金The present study was financially supported by the National Key R&D Program of China(2017YF0502200)the Key Program of the National Natural Science Foundation of China(31630073)+2 种基金the earmarked fund for China Agriculture Research System(CARS-41)the Agricultural Science and Technology Innovation Program,China(ASTIP-IAS09)the earmarked fund for Hebei Chicken Innovation Team of Modern Agro-Industry Technology Research System,China(HBCT2018150203 and HBCT2018150206).
文摘This experiment was conducted to investigate the effect of dietary calcium(Ca)or phosphorus(P)deficiency on bone development and related Ca or P metabolic utilization parameters of broilers from 22 to 42 days of age based on our previous study,which indicated that dietary Ca or P deficiency impaired the bone development by regulating related Ca or P metabolic utilization parameters of broilers from 1 to 21 days of age.A total of 504 one-day-old Arbor Acres male broilers were randomly assigned to 1 of 4 treatments with 7 replicates in a completely randomized design,and fed the normal control and Ca-or P-deficient diets from 1 to 21 days of age.At 22 days of age,the broilers were further fed the normal control diet(0.90%Ca+0.35%non-phytate P(NPP)),the P-deficient diet(0.90%Ca+0.18%NPP),the Ca-deficient diet(0.30%Ca+0.35%NPP)or the Ca and P-deficient diet(0.30%Ca+0.18%NPP),respectively.The results showed that dietary Ca or P deficiency decreased(P<0.05)tibia bone mineral density(BMD),bone breaking strength(BBS),ash content,tibia ash Ca content and serum P content on days 28 and 42,but increased(P<0.05)tibia alkaline phosphatase(ALP)activity of broilers on day 42 compared with the control group.Furthermore,the broilers fed the P-deficient diet had the lowest(P<0.05)tibia BMD,BBS,ash content,serum P content and the highest(P<0.05)serum Ca content on day 28 compared with those fed the Ca-deficient or Ca and P-deficient diets.The results from the present study indicated that the bone development and related Ca or P metabolic utilization parameters of broilers were the most sensitive to dietary P deficiency,followed by dietary Ca deficiency or Ca and P-deficiency;dietary Ca or P deficiency impaired the bone development possibly by regulating serum Ca and P contents as well as tibia Ca content and ALP activity of broilers from 22 to 42 days of age.
基金Supported by A New Investigator Award from the BBSRC
文摘The plasma membrane Ca2+-ATPase(PMCA)is an ATPdriven pump that is critical for the maintenance of low resting[Ca2+]i in all eukaryotic cells.Metabolic stress, either due to inhibition of mitochondrial or glycolytic metabolism,has the capacity to cause ATP depletion and thus inhibit PMCA activity.This has potentially fatal consequences,particularly for non-excitable cells in which the PMCA is the major Ca2+efflux pathway.This is because inhibition of the PMCA inevitably leads to cytosolic Ca2+ overload and the consequent cell death.However,the relationship between metabolic stress,ATP depletion and inhibition of the PMCA is not as simple as one would have originally predicted.There is increasing evidence that metabolic stress can lead to the inhibition of PMCA activity independent of ATP or prior to substantial ATP depletion.In particular,there is evidence that the PMCA has its own glycolytic ATP supply that can fuel the PMCA in the face of impaired mitochondrial function.Moreover, membrane phospholipids,mitochondrial membrane potential,caspase/calpain cleavage and oxidative stress have all been implicated in metabolic stress-induced inhibition of the PMCA.The major focus of this review is to challenge the conventional view of ATP-dependent regulation of the PMCA and bring together some of the alternative or additional mechanisms by which metabolic stress impairs PMCA activity resulting in cytosolic Ca2+ overload and cytotoxicity.
文摘Objective: It remains unknown whether calcium metabolism has any effect on the clinical presentation of superior semicircular canal dehiscence(SSCD). Our aim was to analyse the adjusted calcium and vitamin D levels in SSCD patients compared to a control group.Methods: This was a prospective case-control study performed in a tertiary referral center, university teaching hospital in the UK. It included all new patients with SSCD seen in a dedicated skull base clinic over a 5-year period(2015-2019) compared to a gender and age matched control group. The main outcome of the study was adjusted calcium and Vitamin D levels between the two groups.Results: A total of 31 SSCD patients were recruited with a matched number of control patients. The mean Vitamin D level on the SSCD group was 44.8 nmoL/l(SD: 20.8) compared to 47.5 nmoL/l(SD: 27.4) on the control group(p = 0.702). Mean Adjusted calcium level was 2.34 mmoL/l(SD: 0.7) for SSCD compared to2.41 mmoL/l(SD: 0.11) for controls(p = 0.01), being within normal limits for both the SSCD and the control group.Conclusion: Our study did not identify a link between Vitamin D levels and presence of SSCD. Normal adjusted calcium values were found in both groups. Despite that a statistically significant lower calcium level was found in the SSCD group which could indicate that suboptimal levels of calcium may affect the micro-environment of the otic capsule at the SSC region.
文摘The extensive use of nanoparticles(NPs)in diverse applications causes their localization to aquatic habitats,affecting the metabolic products of primary producers in aquatic ecosystems,such as algae.Synthesized calcium oxide nanoparticles(CaO NPs)are of the scarcely studied NPs.Thus,the current work proposed that the exposure to CaO NPs may instigate metabolic pathway to be higher than that of normally growing algae,and positively stimulate algal biomass.In this respect,this research was undertaken to study the exposure effect of CaO NPs(0,20,40,60,80,and 100μg mL^(−1))on the growth,photosynthesis,respiration,oxidative stress,antioxidants,and lipid production of the microalga Coccomyxa chodatii SAG 216-2.The results showed that the algal growth concomitant with chlorophyll content,photosynthesis,and calcium content increased in response to CaO NPs.The contents of biomolecules such as proteins,amino acids,and carbohydrates were also promoted by CaO NPs with variant degrees.Furthermore,lipid production was enhanced by the applied nanoparticles.CaO NPs induced the accumulation of hydrogen peroxide,while lipid peroxidation was reduced,revealing no oxidative behavior of the applied nanoparticles on alga.Also,CaO NPs have a triggering effect on the antioxidant enzymes such as superoxide dismutase,catalase,ascorbate peroxidase,and guaiacol peroxidase.The results recommended the importance of the level of 60μg mL^(−1) CaO NPs on lipid production(with increasing percentage of 65%compared to control)and the highest dry matter acquisition of C.chodatii.This study recommended the feasibility of an integrated treatment strategy of CaO NPs in augmenting biomass,metabolic up-regulations,and lipid accumulation in C.chodatii.
基金supported by the National Natural Science Foundation of China,Nos.82271222(to ZL),81971012(to ZL),82071189(to XG),and 82201335(to YL)Key Clinical Projects of Peking University Third Hospital,No.BYSYZD2019027(to ZL)。
文摘Mitochondria play an essential role in neural function,such as supporting normal energy metabolism,regulating reactive oxygen species,buffering physiological calcium loads,and maintaining the balance of morphology,subcellular distribution,and overall health through mitochondrial dynamics.Given the recent technological advances in the assessment of mitochondrial structure and functions,mitochondrial dysfunction has been regarded as the early and key pathophysiological mechanism of cognitive disorders such as Alzheimer’s disease,Parkinson’s disease,Huntington’s disease,mild cognitive impairment,and postoperative cognitive dysfunction.This review will focus on the recent advances in mitochondrial medicine and research methodology in the field of cognitive sciences,from the perspectives of energy metabolism,oxidative stress,calcium homeostasis,and mitochondrial dynamics(including fission-fusion,transport,and mitophagy).
