Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: DrugBank:APRD00249 (Mutagen)
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The maternal organism provides the developing embryo with its physical environment, nutrients, and a mechanism for eliminating metabolic wastes. Since the physiological state of the pregnant female affects her ability to provide those requirements for the developing embryo, it is not surprising that there are maternal factors that can affect the wellbeing of the embryo. Extremes of maternal age in both humans and animals have been implicated in growth retardation, as well as autosomal trisomies. The influence of maternal size on fetal size is more pronounced among larger species with longer gestation periods such as humans and domestic animals. A clear relationship between the parity of the mother and potential developmental toxicity in humans has not been established due to the confounding influences of maternal age. Among laboratory rodents, however, it appears that offspring of multiparous animals are at increased risk of developmental toxicity. A variety of infectious agents, particularly viruses, have either been demonstrated or implicated as causes of developmental toxicity. In addition, hyperthermia is a possible confounding factor inherent with maternal infection. Although under experimental conditions hyperthermia is teratogenic in laboratory animals, a causative role for transient hyperthermia, which occurs during febrile states concomitant with infections, cannot be clearly established. Chronic maternal vascular disease states including essential hypertension, heart disease, or diabetes mellitus are likely to contribute to uteroplacental insufficiency and developmental toxicity. Poor maternal nutrition among humans contributes to growth retardation, but not to malformations. The production of "abnormal" maternal antibodies, such as are present in Rh incompatibility, can cause fetal wastage. An important maternal factor in humans is uteroplacental insufficiency, which can occur in normal states like twinning, as well as in abnormal conditions including reduced placental size, chronic maternal hypoxia, or uterine ischemia. Although all these maternal factors can contribute to developmental toxicity, they do not necessarily occur as isolated events. Some developmental toxicants exert deleterious effects within both the embryo and the maternal system.
Teratog Carcinog Mutagen 1987
PMID:Maternal factors in developmental toxicity. 288 3

Evaluation of published human and animal teratology data revealed associations between maternal toxicity and congenital malformations and embryofetal death. This has been reported elsewhere in detail and is herein summarized. Regarding human data, intrauterine deaths were observed to occur in association with 1) maternal homeostatic changes due to phenylketonuria and diabetes and 2) maternal toxicity resulting from alcohol abuse, use of aminopterin, and, possibly, trimethadione. A pattern of malformations that was similar and thus suggestive of a common cause was noticed among malformations attributed to phenylketonuria, diabetes mellitus, aminopterin, alcohol, warfarin, phenytoin, phenobarbital, trimethadione, and valproic acid. On reviewing 234 studies of agents tested in hamsters, mice, rats and rabbits, a fairly strong association between maternal toxicity and embryo-fetal mortality was observed. Further, a consistent pattern of fetal malformations associated with maternotoxic effects was discovered in a survey of 476 studies of agents tested in these four species. In these reviews, it was postulated that maternal toxicity per se could possibly cause such fetal effects. For evaluating maternotoxic effects in experimental studies, the minimum maternal data required would be frequent measurements of maternal body weight and food consumption, signs of altered behavior, death, and gross lesions at necropsy.
Teratog Carcinog Mutagen 1987
PMID:Maternal toxicity in humans and animals: effects on fetal development and criteria for detection. 288 7

The contribution of induced mutations to the burden of genetic disease in the context of population genetics is considered. A clear distinction is made between the effects of genetic disease and mutational events. Much of the existing burden of genetic disease is a consequence of mutations that occurred in the past. The problem of distinguishing between spontaneous and induced mutations is discussed. Molecular genetics techniques are blurring the definitions of these terms. Classical population genetics shows that the frequency of affected individuals will reach an equilibrium depending on the mutation rate and the selective pressure against affected individuals. Increasing the mutation rate or reducing the selective pressures would result in a new equilibrium with an increase in the frequency in subsequent generations of affected individuals with dominant and X-linked mutant alleles. The increase in the number of recessive mutant alleles would be much slower and take many generations to reach the new equilibrium level. One assumption behind such equilibria is random mating. Changes in human demography with a rapid increase in population size, the breakup of small, relatively inbred subpopulations, and relaxed selective pressures will lead to a new equilibrium for recessive genes at probably higher frequencies. These factors will be the major contributors to increasing the burden of recessive genetic disease by increasing the total numbers of cases. The proportion of the population with a genetic disease will also continue to grow as a greater proportion of the population survives to late middle age and succumbs to diseases associated with old age, such as cancer, circulatory disease, dementias, and diabetes, each of which is likely to have a genetic component.(ABSTRACT TRUNCATED AT 250 WORDS)
Environ Mol Mutagen 1995
PMID:Population genetics of induced mutations. 778 63

To determine the effect of maternal diabetes and alcohol intake, separately and in combination, on fetal growth and development, pregnant rats were divided into four groups: diabetic (D), diabetic plus alcohol (DA), control (C), and control plus alcohol (CA). Diabetes was induced by administration of streptozotocin before mating and alcohol was administered by gavage (2 g/kg body weight/day) on days 6-11 of gestation. Both diabetic groups (D and DA) had significantly lower weight gain during pregnancy compared to the controls (C and CA), despite the fact that the former consumed more food and water. Alcohol treatment resulted in reduced water and food intake and lower weight gain in the diabetic rats (DA), but not in the non-diabetic rats (CA), compared to their respective controls (D and C). On day 21 of gestation fetal body weights were significantly less and placental weights were significantly greater in the diabetic groups (D and DA) compared with the non-diabetic groups (C and CA). Differences in fetal and placental weights between rats exposed and not exposed to alcohol (C vs. CA and D vs. DA) were not significant. The number of fetuses with external malformations was significantly greater in the litters of alcohol exposed diabetic (DA) than non-alcohol exposed (D) animals. No external or skeletal malformations were observed in fetuses of non-diabetic rats regardless of whether or not they received alcohol (C or CA). The skeletal development of fetuses of diabetic rats, judged by the number and size of ossification centers on day 21 of gestation, was retarded when compared with fetuses of non-diabetic rats. Alcohol further retarded skeletal development of fetuses of diabetic animals (DA vs. D), but not of fetuses of non-diabetic rats (CA vs. C). It is concluded that maternal alcohol administration potentiates the effects of maternal diabetes on the incidence of fetal malformations and the retardation of skeletal development.
Teratog Carcinog Mutagen 1995
PMID:Interactive effects of alcohol and diabetes during pregnancy on the rat fetus. 858 86

Thalassaemia is a group of genetic diseases where haemoglobin synthesis is impaired. This chronic anaemia leads to increased dietary iron absorption, which develops into iron overload pathology. Treatment through regular transfusions increases oxygen capacity but also provides iron through the red cells' haemoglobin. An essential treatment, in parallel with transfusions, is the use of chelating agents to remove the excess iron deposited in tissues. These deposits are found in the liver, spleen, heart, and pancreas and are associated with cardiac failure and diabetes. The deposits in these tissues of patients have been isolated as haemosiderin. Thalassaemia patients are particularly at risk of free radical induced damage. Thus, the present study has investigated, as a model system, human cells in vitro in the Comet assay in the presence of free radicals. This assay measures DNA damage, particularly DNA strand breakage. The effects of iron overload on cells oxidatively stressed with hydrogen peroxide (H(2)O(2)) have been determined as well as the effect of the chelating agent, deferoxamine. Iron overload was simulated with ferric (FeCl(3)) and ferrous chloride (FeCl(2)), ferrous sulphate (FeSO(4)) and haemosiderins. Both human lymphocytes from a male and a female donor and human adenocarcinoma colonic cells showed an increase in DNA damage in the Comet assay after treatment with H(2)O(2). Ferric chloride produced an increase in DNA damage in human colonic cells, but little or no damage in human lymphocytes. Ferrous chloride also produced weak DNA damage in human lymphocytes, but ferrous sulphate produced a dose-related response. Deferoxamine produced no DNA damage. When H(2)O(2) was combined with FeCl(3), FeCl(2), or FeSO(4), the DNA damage produced was as least as great as or slightly greater than with H(2)O(2) alone. When deferoxamine was combined with H(2)O(2) and FeSO(4) there was a consistent decrease in response. There was little or no decrease in response when deferoxamine was combined with H(2)O(2) and FeCl(3) or FeCl(2), but at high (100-300microm) doses there were changes in the appearance of cellular DNA from Comet tails to dense centres surrounded by a diffuse area. This was probably as a consequence of chelation processes. Haemosiderin produced no damage. The three fractions of haemosiderin examined were of three different densities and from a Thai patient where the oxyhydroxide phase is the ferrihydrite. The colour change was similar to that for FeCl(3), but the level of the ferric ion in the haemosiderin was possibly too low in the sample to produce a response. The next stage is to examine peripheral lymphocytes from thalassaemic patients, with and without chelation therapy, whose cells may be more sensitive to simulated iron overload and to lower levels of haemosiderin. Teratogenesis Carcinog. Mutagen. 20:11-26, 2000.
Teratog Carcinog Mutagen 2000
PMID:Effects of iron salts and haemosiderin from a thalassaemia patient on oxygen radical damage as measured in the comet assay. 1060 74

The etiology of pancreatic cancer is poorly understood, partly because of the inconsistency of findings among case-control studies of pancreatic cancer. Because of the unfavorable prognosis for pancreatic cancer, many case-control studies have been based largely on interviews with next of kin, who are known to report less reliable information on potential risk factors than original respondents. The purpose of this study was to estimate the effects of speculative risk factors such as dietary/nutritional factors and alcohol drinking, as well as those of established risk factors such as cigarette smoking, diabetes mellitus, and family history of pancreatic cancer, on pancreatic cancer risk based solely on direct interviews. This investigation was a population-based case-control study of pancreatic cancer diagnosed in Atlanta (GA), Detroit (MI), and ten New Jersey counties from August 1986 through April 1989. Direct interviews were conducted with 526 incident cases and 2,153 population controls. This study revealed a significant interaction between body mass index and caloric intake that was consistent by both race and gender. Subjects with elevated body mass index and caloric intake had increased risk, whereas those with elevated values for one of these factors but not the other experienced no increased risk. This finding suggests that energy balance may play a major role in pancreatic carcinogenesis. Diabetes mellitus was also a risk factor for pancreatic cancer, as well as a possible complication of the tumor. Our data are consistent with a key role for hyperinsulinemia in pancreatic carcinogenesis, particularly among non-diabetics with an elevated body mass index. A three-fold risk of pancreatic cancer among first-degree relatives of affected individuals was apparent. An increased risk also was associated with a family history of colon, endometrial, ovary, and breast cancer, suggesting a possible link to hereditary non-polyposis colon cancer. Our findings support a causal role for cigarette smoking in pancreatic carcinogenesis. Alcohol drinking at levels typically consumed by the general population of the United States did not appear to be a risk factor for pancreatic cancer, although heavy drinking may be related to risk, particularly in blacks.
Teratog Carcinog Mutagen 2001
PMID:Risk factors for pancreatic cancer: a case-control study based on direct interviews. 1113 18

Abnormal glucose tolerance and frank diabetes mellitus develop in up to 80% of pancreatic cancer patients. Islets within these tumors show a decreased number of beta cells and increased number of alpha cells. The reduced number of beta cells could induce beta cell neogenesis in extrainsular tissue to compensate for the loss of insulin in islets. On the other hand, because the beta cell depletion in pancreatic cancer seems to be the effect of substances released by cancer cells, suppression of extrainsular endocrine cells is expected. We compared the pattern of extrainsular endocrine cells in pancreatic cancer patients with normal pancreas as well as chronic pancreatitis, which is known to be associated with impaired glucose tolerance or frank diabetes. As in the normal tissue, extrainsular endocrine cells were found in chronic pancreatitis and pancreatic cancer. However, in the chronic pancreatitis specimens insulin cells were the predominant cell type, whereas in pancreatic cancer specimens more glucagon than insulin cells were found, although the differences were statistically insignificant. Thus, our results indicate that the alteration of beta cells in pancreatic cancer patients is mainly restricted to the endocrine cells within the islets and that there is no compensatory proliferation of beta cells.
Teratog Carcinog Mutagen 2001
PMID:The patterns of extrainsular endocrine cells in pancreatic cancer. 1113 22

Early embryonic deaths as well as malformed newborns are among complications of the diabetic pregnancy. Cytokines and growth factors operating in the embryonic vicinity are found to be among factors that determine the sensitivity of embryos to external and internal detrimental stimuli, including diabetes. Transforming Growth Factor-beta2 (TGF-beta2) has been shown to be essential for embryonic development and survival. In the present work, we evaluated the pattern of TGF-beta2 expression in the uterus of streptozotocin-induced diabetic mice, demonstrating a decreased reproductive performance and elevated percentage of litters with severely malformed fetuses. Since stimulation of the maternal immune system was found to increase the resistance of mouse embryos to the teratogenic effect of diabetes, the effect of immunopotentiation on the expression of the cytokine was also investigated. TGF-beta2 expression was studied at the mRNA level by using the in situ hybridization technique and at the protein level by using the immunohistochemical analysis. A clear decrease in TGF-beta2 mRNA expression in the uterus of diabetic mice was observed at examined time points: days 1, 5, and 9 of pregnancy. Also, an evident reduction in TGF-beta2, the protein expression in the uterus of diabetic mice, was demonstrated at these time points. Maternal immunopotentiation that improved the reproductive performance of diabetic mice and reduced the number of the litters with malformed fetuses was also accompanied by a clear increase in the level of TGF-beta2 mRNA expression in the pregnant uteri. The above results clearly demonstrate that the embryotoxic effect of diabetes is accompanied by an alteration of TGF-beta2 expression. Immunopotentiation that was shown to improve the reproductive performance of the diabetic mice was accompanied by a partial normalization of TGF-beta2 expression in embryonic vicinity.
Teratog Carcinog Mutagen 2002
PMID:Diabetes teratogenicity in mice is accompanied with distorted expression of TGF-beta2 in the uterus. 1194 34

Recent publications have reported a weak but consistent correlation between diabetes incidence and occupational or accidental exposure to dioxins. As with most work involving environmental xenobiotics, these studies suffered from the analytical problem that the reference populations had some degree of exposure. We have used Haber's Rule to relate the integrated exposure of subjects involved in an industrial exposure to dioxins, reported by Sweeney et al. [Teratog. Carcinog. Mutagen. 17 (1998) 241], to the incremental probability of diabetes incidence. We estimated that background exposure to dioxin-like compounds by the referents contributed <1% of their diabetes risk, suggesting that background exposure to dioxins is not a significant risk factor for individuals who have not been occupationally or accidentally exposed.
 ...
PMID:Use of Haber's Rule to estimate the risk of diabetes from background exposures to dioxin-like compounds. 1199 35

The nuclear DNA transcriptional programming of the mitochondria proteome varies dramatically between tissues depending on its functional requirements. This programming generally regulates all of the proteins associated with a metabolic or biosynthetic pathway associated with a given function, essentially regulating the maximum rate of the pathway while keeping the enzymes at the same molar ratio. This may permit the same regulatory mechanisms to function at low- and high-flux capacity situations. This alteration in total protein content results in rather dramatic changes in the mitochondria proteome between tissues. A tissues mitochondria proteome also changes with disease state, in Type 1 diabetes the liver mitochondrial proteome shifts to support ATP production, urea synthesis, and fatty acid oxidation. Acute flux regulation is modulated by numerous posttranslational events that also are highly variable between tissues. The most studied posttranslational modification is protein phosphorylation, which is found all of the complexes of oxidative phosphorylation and most of the major metabolic pathways. The functional significance of these modifications is currently a major area of research along with the kinase and phosphatase regulatory network. This near ubiquitous presence of protein phosphorylations, and other posttranslational events, in the matrix suggest that not all posttranslational events have functional significance. Screening methods are being introduced to detect the active or dynamic posttranslational sites to focus attention on sites that might provide insight into regulatory mechanisms.
Environ Mol Mutagen 2010 Jun
PMID:The mitochondrial proteome: a dynamic functional program in tissues and disease states. 2054 78


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