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Higher plants can adapt to abiotic stress to a certain degree. In this study, the impact of temperature stress on osmotic stress adapted and un-adapted cell lines of rice (Oryza sativa L.cv Swat-1) was observed. For the change in proline content, relative growth rate, saturated and unsaturated fatty acid were evaluated. The cell lines were incrementally adapted to 20% polyethylene glycol. The adapted lines showed significantly higher growth rate and proline content as compared to the un-adapted cell lines on temperature stress. Among saturated fatty acids palmitic acid (C16:0), stearic acid (C18:0) and myristic acid (C14:0) were the prominent fatty acids detected while among unsaturated fatty acid Oleic acid (C18:1c) and Linoleic acid (C18:2c) were the major fatty acids found. Under low temperature stress the percentage of saturated fatty acids was found to be lower (53%) in adapted cell line as compared to the un-adapted cell line (63%) while the percentage of saturation increased (83%) in adapted line under high temperature stress as compared to un-adapted line (70%). On the other hand at low temperature stress the percent level of unsaturated fatty acids in the adapted line was higher (48%) than the un-adapted cell line (37%). In conclusion, adaptation to one abiotic stress confers co-tolerance to the other abiotic stresses. Fatty acids saturation level could be a crucial factor in the plant ability to tolerate heat and cold stress.

Levels of sodium (Na+), potassium (K+), calcium (Ca+2) and magnesium (Mg+2) ions were determined in the root, leaf and petiole of cultivated Sassurea lappa plant collected from Pakistan Forest Institute, Peshawar. The same ions were also analyzed in root (b) of the same plant collected from Koza Gali, Abbottabad as well as in wild plant root (c) of Kashmir hills. Potassium (K+) and sodium (Na+) in the medicinal plant, S. lappa were determined by using flame photometer (Jenway PFP 7) while Ca+2 and Mg+2 contents were measured by atomic absorption spectrophotometer (Hitachi Z-800). Significant differences were observed among all the tested samples. However, the highest level of K+ was 1886.45 µMg-1 found in cultivated plant petiole and its lowest concentration was 385.351 µMg-1 observed in shoot derived callus (callus a). Sodium content (Na+) was found higher in shoot callus (callus a) while magnesium (Mg+2) concentration was observed high (109.349 µMg-1) in root (b) collected from Koza Gali, Abbottabad and their lower concentrations were 102 µMg-1 and 47.432 µMg-1 found in petiole and wild plant root (root c) respectively. The lowest concentration was found in case of Ca+2 in comparison of other elements. The levels of all the selected elements were highly varied in the anatomical parts of the same cultivated plant, shoot and root derived calli and between the varied regions plant roots except Ca+2. The overall levels of the elements were found in the order: K+ > Na+ > Mg+2 > Ca+2. Keywords: Saussurea lappa; In vitro culture; Calli; Major elements http://dx.doi.org/10.19045/bspab.2019.80087

Thermal stress induces a wide array of morphological and physiological changes in potato affecting its development and economic yield. Response to thermal stress in plants is mostly regulated by heat shock factors (hsfs). The current study aimed at improving heat tolerance by transforming potato plant with heat shock factor, HsfA1d, using Agrobacterium. Gateway cloning strategy was adopted for isolation of HsfA1d from Arabidopsis thaliana and cloning into plant expression vector. The target gene was introduced into potato by infecting internodal explants with Agrobacterium strain GV3101 carrying pGWB402Ω-HsfA1d construct. Upon exposure to heat stress, the wild-type plants turned yellowish, whereas no phenotypic effect on transgenic plants was observed. Expression of HsfA1d in transgenic plants was increased by 5.8-fold under thermal stress compared to room temperature. Transgenic plants exhibited 6-fold increase in the expression of downstream HSP70 under thermal stress compared to wild-type plants. Both chlorophyll a and b were significantly decreased in wild-type plants while no such decrease was recorded in transgenic plants under thermal stress. Heat stress was found to have no significant effect on carotenoid pigments of both wild-type and transgenic plants. Significantly lower electrolyte leakage from transgenic plants was witnessed compared to wild type upon exposure to thermal stress. Transgenic plants accumulated significantly higher proline content compared to wild-type plants under heat stress. It is concluded that HsfA1d plays a vital role in plant thermotolerance and hence can be effectively used to enhance the resistance of crop plants against heat stress. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s12192-019-01043-6) contains supplementary material, which is available to authorized users.

2 Abstract: The effect of cinnamon on blood glucose and lipid profile was studied in type-2 diabetic individuals for 30 days. Fourteen diabetic individuals of both sexes and of age 40 and above were divided in two groups, each having 7 individuals. Group 1 was assigned for 1.5 g cinnamon dose/day while group 2 was assigned for 1.5g placebo dose/day. The doses were given for 30 days. Fasting blood samples were collected at the start of experiment (day 0) and at the end of experiment (day 30). Serum glucose, serum triglycerides, serum total cholesterol, high density lipoprotein HDL and low density lipoprotein LDL cholesterol, of both cinnamon and placebo groups were determined. The results showed that cinnamon dose significantly reduced glucose, triglycerides and cholesterol. HDL and LDL cholesterol were not affected. Placebo did not affect any of the above parameters.

As breast cancer cells often develop chemoresistance, better therapeutic options are in search to circumvent it. Here we demonstrate that human epidermal growth factor receptor-2 (HER-2)-overexpressing breast cancer cells resist docetaxel-induced cytotoxicity by upregulating HER-2 and its activity downstream, through Akt and mitogen-activated protein kinase (MAPK) pathways. We observed that introducing resveratrol as a chemosensitizer in docetaxel chemotherapy blocks upregulation and activation of HER-2 in addition to blocking downstream signaling pathways such as Akt. Resveratrol and docetaxel combination results in the synergistic induction of cell death in HER-2-overexpressing SK-BR-3 cells, whereas introduction of wild-type HER-2 in MDA-MD-231 cells increased the resistance to docetaxel. Dominant-negative HER-2 sensitizes SK-BR-3 cells to docetaxel. Our study identified a new synergistic therapeutic combination that targets HER-2-induced breast cancer resistance and might help to overcome therapeutic resistance during breast cancer therapy. The synergism of docetaxel and resveratrol was maximum in SK-BR-3, which is unique among the cell lines studied, due to its high expression status of HER-2, a receptor known to dictate the signaling environment of breast cancer cells. Docetaxel could further induce HER-2 activity in these cells, which was downregulated on resveratrol treatment. Transfection of DN-HER-2 in SK-BR-3 cells inhibits the synergism as the transfection itself sensitizes these cells to docetaxel, leaving no role for resveratrol, whereas ectopic expression of HER-2 introduces the synergism in MDA-MB-231, the triple-negative cell line, in which the synergism was minimum, attesting the crucial role of HER-2 in suppressing the sensitivity to docetaxel. Single-agent docetaxel induced HER-2-mediated resistance to cell death, which was blocked by resveratrol. Resveratrol also downregulated docetaxel-induced activation of MAPK and Akt, survival signaling pathways downstream of HER-2. In short, this study, for the first time, establishes the role of HER-2–Akt signaling axis in regulating the synergistic effect of docetaxel and resveratrol in breast cancer cells overexpressing HER-2.

Cell lines of Oryza sativa L. (cv. Taipei-309) were adapted to 30 mM LiCl and 150 mM NaCl. Both adapted lines were considerably more tolerant than non adapted line when grown on 200, 250 and 300 mM NaCl and 30 mM LiCl stresses. The tolerance of LiCl-adapted line to NaCl (150 to 300 mM) and the tolerance of NaCl-adapted cells line to LiCl (30 mM) indicated that there was a cross-adaptation towards alkali metals (Na+ and Li+) not the Cl−. Na+ and K+ contents of all lines which increased with increasing medium salinity but to a different degree. The increase in Na+ and K+ content in NaCl-adapted and non-adapted lines were comparable, while LiCl-adapted line accumulated significantly lower Na+and higher K+ content. Proline content of all lines increased with the increase in NaCl-stress but the magnitude of increase was much higher in the LiCl-adapted than other lines. The differential response of adapted lines to NaCl stress in accumulating proline and maintaining the ionic contents reveals that adapted lines have evolved different features of adaptation to cope with NaCl stress.

Callus cultures established from a cotyledon explant of Medicago sativa L. cv. Dupuits were used as the inoculum for the establishment of suspension cell-cultures. The cell suspension cultures were grown on selection media of increasing NaCl concentration and a culture growing rapidly at 350 mol m −3 NaCl was obtained. Callus cultures derived from NaCl-selected suspension cultures grew slowly at 350 mol m −3 NaCl but growth was unaffected at 250 mol m −3 NaCl whereas growth of callus cultures derived from unselected cells was completely inhibited at 350 mol m −3 NaCl and 90% inhibited at 250 mol m −3 NaCl. The NaCl-tolerant callus was considerably more tolerant to the chlorides of all the alkali-metals than the non-selected callus as shown by good growth at concentrations of alkali-metal chlorides that inhibited growth of non-selected cells. This tolerance was towards the alkali-metals, not the Cl − ion, and shows that cotolerance to other alkali-metals is imposed by the selection of tolerance to Na + .

Wheat is notorious for callus induction, which is a major hindrance in direct gene transfer and consequently for genetic improvement programs. In order to provide a successful platform for gene transformation, good callus quantity and quality is important. We investigated the variation in callus induction capabilities of Pakistani wheat cultivars and measured the reducing sugar content in the induced calluses. Ten elite wheat varieties, developed and cultivated in Pakistan were selected on the basis of agronomic and stress tolerance parameters. Significant differences were found between and among wheat cultivars for callus induction response, shoot length and callus quality. The callus induction responses of Punjab-81, Punjab-96 and Zarghoon-79 were found to be the best among the 10 varieties. The induced calluses were of two types, embryogenic (hard) and non-embryogenic (soft). The seeds gave good germination. The highest reducing sugar concentration was found in cultivar Sutlaj-86, which needs to be tested for stress resistance, a measure of its utility for genetic engineering programs. The relative callus induction rate and reducing sugar content of the wheat cultivars were found to be genotype-dependent.

SUMMARY Callus cultures, established from cultivars of Medicago sativa L., Dupuits and Spredor2, were used to investigate salt-induced changes in metabolism. With increase in NaCl concentration there was a progressive reduction in growth rate but this effect was ameliorated by increase in the Ca2+ concentration. The concentration of Na+ in the callus increased in response to NaCl in the medium but not proportionally, while the K+ concentration was lowest in calli grown at the highest NaCl concentration. High Ca2+ partially reversed the salt-induced decrease in K+, so overall, the effect of Ca2+ was to decrease the Na+/K+ ratio. Proline concentration in the callus increased in response to NaCl. With callus cultures grown in the absence of supplemental NaCl there was no correlation between growth and proline concentration, whereas at the highest NaCl concentration used (150 mol m−3) there was a strong positive correlation between growth and proline concentration of individual calli. Increased Ca2+increased the proline concentration in callus of both cultivars, and at the highest salt concentration resulted in higher proline concentration and increased growth. It is suggested that proline accumulation is important for cell growth only when a certain level of salt-stress is attained, and this level will depend on the presence or absence of other protectant mechanisms in the tissue.