There were errors published in J. Cell Sci. 124, 2143Sci. 124, -2152 In the section given below, PtdIns(3,4,5)P 3 was on four occasions incorrectly printed instead of the correct Ins(1,4,5)P 3 .We apologise for this mistake. Increased mitochondrial Ca2+ drives the adaptive metabolic boost observed during early phases of ER stress Increases in mitochondrial respiration and ATP production are often consequences of increases in mitochondrial Ca 2+ (Green and Wang, 2010). In order to determine whether early phases of ER stress induced by tunicamycin increased mitochondrial Ca 2+ , we treated cells expressing cytosolic or mitochondrial aequorins with histamine [which evokes Ins(1,4,5)P 3 -dependent Ca2+ release] and compared their mitochondrial Ca 2+ uptake. We observed that histamine led to a mitochondrial Ca 2+ uptake that was significantly higher in tunicamycinpretreated cells (P<0.05; 4 hours) than in untreated cells (Fig. 6A). Cytosolic Ca 2+ increased similarly in tunicamycin-treated and untreated cells (Fig. 6B). These results indicate that the differences in mitochondrial Ca 2+ levels are not due to altered Ca 2+ release mediated by the Ins(1,4,5)P 3 receptor but to an enhanced mitochondrial Ca 2+ uptake, presumably due to the increased apposition of ER and mitochondrial Ca 2+ channels. By using a different dye, Fura-2, we monitored the peak cytosolic Ca 2+ levels after thapsigargin addition, reflecting the kinetics of Ca 2+ release after sarcoplasmic/endoplasmic reticulum Ca 2+ -ATPase (SERCA) inhibition. After 4 hours of tunicamycin treatment, the thapsigargin-induced Ca 2+ peak was increased, and it was further elevated by inhibition of mitochondrial Ca 2+ uptake using Ru360 (Fig. 6C). These results suggest that, besides the Ins(1,4,5)P 3 -receptor-mediated direct Ca 2+ transfer from the ER to neighboring mitochondria, an additional phenomenon associated with the early phases of ER stress involves Ca 2+ leak from the ER, also resulting in mitochondrial Ca 2+ uptake. Indeed, no mitochondrial Ca 2+ uptake following the thapsigargin-induced Ca 2+ leak was observed in Mfn2-knockout cells (Fig. 6D), which is reflected by the lack of effect of Ru360. This result further indicates that juxtaposition of mitochondria with the ER is necessary for the mitochondrial Ca 2+ uptake evoked by Ca 2+ leak during early phases of ER stress.Finally, to test whether mitochondrial Ca 2+ levels control the metabolic mitochondrial boost, we measured oxygen consumption rates resulting from OXPHOS in the presence of the Ins(1,4,5)P 3 receptor inhibitor xestospongin B or the mitochondrial Ca 2+ uptake inhibitor RuRed. We observed that both xestospongin B and RuRed decreased the rate of oxygen consumption after tunicamycin treatment (Fig. 7A,B), which confirms that increased mitochondrial Ca 2+ uptake, resulting from ER-mitochondrial coupling, is necessary for the metabolic response observed during early phases of ER stress. Therefore, in order to evaluate whether the early metabolic boost forms part of an adaptive response triggere...

Artemisia annua is currently the only commercial source of the sesquiterpene lactone artemisinin. Since artemisinin was discovered as the active component of A. annua in early 1970s, hundreds of papers have focused on the anti-parasitic effects of artemisinin and its semi-synthetic analogs dihydroartemisinin, artemether, arteether, and artesunate. Artemisinin per se has not been used in mainstream clinical practice due to its poor bioavailability when compared to its analogs. In the past decade, the work with artemisinin-based compounds has expanded to their anti-cancer properties. Although artemisinin is a major bioactive component present in the traditional Chinese herbal preparations (tea), leaf flavonoids, also present in the tea, have shown a variety of biological activities and may synergize the effects of artemisinin against malaria and cancer. However, only a few studies have focused on the potential synergistic effects between flavonoids and artemisinin. The resurgent idea that multi-component drug therapy might be better than monotherapy is illustrated by the recent resolution of the World Health Organization to support artemisinin-based combination therapies (ACT), instead of the previously used monotherapy with artemisinins. In this critical review we will discuss OPEN ACCESSMolecules 2010, 15 3136 the possibility that artemisinin and its semi-synthetic analogs might become more effective to treat parasitic diseases (such as malaria) and cancer if simultaneously delivered with flavonoids. The flavonoids present in A. annua leaves have been linked to suppression of CYP450 enzymes responsible for altering the absorption and metabolism of artemisinin in the body, but also have been linked to a beneficial immunomodulatory activity in subjects afflicted with parasitic and chronic diseases.

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Insulin regulates heart metabolism through the regulation of insulin-stimulated glucose uptake. Studies have indicated that insulin can also regulate mitochondrial function. Relevant to this idea, mitochondrial function is impaired in diabetic individuals. Furthermore, the expression of Opa-1 and mitofusins, proteins of the mitochondrial fusion machinery, is dramatically altered in obese and insulin-resistant patients. Given the role of insulin in the control of cardiac energetics, the goal of this study was to investigate whether insulin affects mitochondrial dynamics in cardiomyocytes. Confocal microscopy and the mitochondrial dye MitoTracker Green were used to obtain three-dimensional images of the mitochondrial network in cardiomyocytes and L6 skeletal muscle cells in culture. Three hours of insulin treatment increased Opa-1 protein levels, promoted mitochondrial fusion, increased mitochondrial membrane potential, and elevated both intracellular ATP levels and oxygen consumption in cardiomyocytes in vitro and in vivo. Consequently, the silencing of Opa-1 or Mfn2 prevented all the metabolic effects triggered by insulin. We also provide evidence indicating that insulin increases mitochondrial function in cardiomyocytes through the Akt-mTOR-NFκB signaling pathway. These data demonstrate for the first time in our knowledge that insulin acutely regulates mitochondrial metabolism in cardiomyocytes through a mechanism that depends on increased mitochondrial fusion, Opa-1, and the Akt-mTOR-NFκB pathway.

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There were errors published in J. Cell Sci. 124, 2143Sci. 124, -2152 In the section given below, PtdIns(3,4,5)P 3 was on four occasions incorrectly printed instead of the correct Ins(1,4,5)P 3 .We apologise for this mistake. Increased mitochondrial Ca2+ drives the adaptive metabolic boost observed during early phases of ER stress Increases in mitochondrial respiration and ATP production are often consequences of increases in mitochondrial Ca 2+ (Green and Wang, 2010). In order to determine whether early phases of ER stress induced by tunicamycin increased mitochondrial Ca 2+ , we treated cells expressing cytosolic or mitochondrial aequorins with histamine [which evokes Ins(1,4,5)P 3 -dependent Ca2+ release] and compared their mitochondrial Ca 2+ uptake. We observed that histamine led to a mitochondrial Ca 2+ uptake that was significantly higher in tunicamycinpretreated cells (P<0.05; 4 hours) than in untreated cells (Fig. 6A). Cytosolic Ca 2+ increased similarly in tunicamycin-treated and untreated cells (Fig. 6B). These results indicate that the differences in mitochondrial Ca 2+ levels are not due to altered Ca 2+ release mediated by the Ins(1,4,5)P 3 receptor but to an enhanced mitochondrial Ca 2+ uptake, presumably due to the increased apposition of ER and mitochondrial Ca 2+ channels. By using a different dye, Fura-2, we monitored the peak cytosolic Ca 2+ levels after thapsigargin addition, reflecting the kinetics of Ca 2+ release after sarcoplasmic/endoplasmic reticulum Ca 2+ -ATPase (SERCA) inhibition. After 4 hours of tunicamycin treatment, the thapsigargin-induced Ca 2+ peak was increased, and it was further elevated by inhibition of mitochondrial Ca 2+ uptake using Ru360 (Fig. 6C). These results suggest that, besides the Ins(1,4,5)P 3 -receptor-mediated direct Ca 2+ transfer from the ER to neighboring mitochondria, an additional phenomenon associated with the early phases of ER stress involves Ca 2+ leak from the ER, also resulting in mitochondrial Ca 2+ uptake. Indeed, no mitochondrial Ca 2+ uptake following the thapsigargin-induced Ca 2+ leak was observed in Mfn2-knockout cells (Fig. 6D), which is reflected by the lack of effect of Ru360. This result further indicates that juxtaposition of mitochondria with the ER is necessary for the mitochondrial Ca 2+ uptake evoked by Ca 2+ leak during early phases of ER stress.Finally, to test whether mitochondrial Ca 2+ levels control the metabolic mitochondrial boost, we measured oxygen consumption rates resulting from OXPHOS in the presence of the Ins(1,4,5)P 3 receptor inhibitor xestospongin B or the mitochondrial Ca 2+ uptake inhibitor RuRed. We observed that both xestospongin B and RuRed decreased the rate of oxygen consumption after tunicamycin treatment (Fig. 7A,B), which confirms that increased mitochondrial Ca 2+ uptake, resulting from ER-mitochondrial coupling, is necessary for the metabolic response observed during early phases of ER stress. Therefore, in order to evaluate whether the early metabolic boost forms part of an adaptive response trigger...

A lactating cow trial was conducted to study the effects of dietary addition of oregano leaf material (Origanum vulgare L.; OV; 0, control vs. 500 g/d) on ruminal fermentation, methane production, total tract digestibility, manure gas emissions, N metabolism, organoleptic characteristics of milk, and dairy cow performance. Eight primiparous and multiparous Holstein cows (6 of which were ruminally cannulated) were used in a crossover design trial with two 21-d periods. Cows were fed once daily. The OV material was top-dressed and mixed with a portion of the total mixed ration. Cows averaged 80 ± 12.5 d in milk at the beginning of the trial. Rumen pH, concentration of total and individual volatile fatty acids, microbial protein outflow, and microbial profiles were not affected by treatment. Ruminal ammonia-N concentration was increased by OV compared with the control (5.3 vs. 4.3mM). Rumen methane production, which was measured only within 8h after feeding, was decreased by OV. Intake of dry matter (average of 26.6 ± 0.83 kg/d) and apparent total tract digestibly of nutrients did not differ between treatments. Average milk yield, milk protein, lactose, and milk urea nitrogen concentrations were unaffected by treatment. Milk fat content was increased and 3.5% fat-corrected milk yield tended to be increased by OV, compared with the control (3.29 vs. 3.12% and 42.4 vs. 41.0 kg/d, respectively). Fat-corrected (3.5%) milk feed efficiency and milk net energy for lactation (NE(L)) efficiency (milk NE(L) ÷ NE(L) intake) were increased by OV compared with the control (1.64 vs. 1.54 kg/kg and 68.0 vs. 64.4%, respectively). Milk sensory parameters were not affected by treatment. Urinary and fecal N losses, and manure ammonia and methane emissions were unaffected by treatment. Under the current experimental conditions, supplementation of dairy cow diets with 500 g/d of OV increased milk fat concentration, feed and milk NE(L) efficiencies, and tended to increase 3.5% fat-corrected milk yield. The sizable decrease in rumen methane production with the OV supplementation occurred within 8h after feeding and has to be interpreted with caution due to the large within- and between-animal variability in methane emission estimates. The OV was introduced into the rumen as a pulse dose at the time of feeding, thus most likely having larger effect on methane production during the period when methane data were collected. It is unlikely that methane production will be affected to the same extent throughout the entire feeding cycle.