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The health of ecosystems and human health are closely linked. Interdisciplinary approaches and initiatives such as "One-Health," "EcoHealth," and, more recently, "Planetary Health" articulate this link. The three concepts are based on recognizing the interdependence between living organisms, both human and non-human, and their ecosystems. And yet, we are living in a time when human activity is leading to a profound degradation of the environment all over the world. Nine planetary boundaries for earth system processes have been proposed who's critical thresholds should not be crossed if we want to maintain our ecosystems and avoid risk of unwelcome outcomes: 1) climate change, 2) loss of biodiversity, 3) disturbances in biogeochemical cycles of nitrogen and phosphorus, 4) deforestation and changes in land use, 5) chemical pollution, 6) ocean acidification, 7) depletion of the ozone layer, 8) the degradation of drinking water, and 9) aerosol pollution. These "planetary bounderies" are suggested to represent a framework within which human activity can develop safely while still allowing the Earth systems to function sustainably. Yet several of these thresholds have already been crossed or are in a risky zone of uncertainty. This is all the more worrying because the connect ions between these various forms of environmental degradation and to human health are nonlinear and complex.

The health of ecosystems and human health are closely linked. Interdisciplinary approaches and initiatives such as "One-Health," "EcoHealth," and, more recently, "Planetary Health" articulate this link. The three concepts are based on recognizing the interdependence between living organisms, both human and non-human, and their ecosystems. And yet, we are living in a time when human activity is leading to a profound degradation of the environment all over the world. Nine planetary boundaries for earth system processes have been proposed who's critical thresholds should not be crossed if we want to maintain our ecosystems and avoid risk of unwelcome outcomes: 1) climate change, 2) loss of biodiversity, 3) disturbances in biogeochemical cycles of nitrogen and phosphorus, 4) deforestation and changes in land use, 5) chemical pollution, 6) ocean acidification, 7) depletion of the ozone layer, 8) the degradation of drinking water, and 9) aerosol pollution. These "planetary bounderies" are suggested to represent a framework within which human activity can develop safely while still allowing the Earth systems to function sustainably. Yet several of these thresholds have already been crossed or are in a risky zone of uncertainty. This is all the more worrying because the connect ions between these various forms of environmental degradation and to human health are nonlinear and complex.

Global warming is considered by most scientists as one of the greatest public health threats of the 21st century. Some individual behaviours and consumption habits related to the food and mobility sectors are responsible for a high amount of CO2 emissions, the main greenhouse gas. Thus, some messages promoted by health professionals will have an impact on the fight against the epidemic of lifestyle-related chronic diseases but will also have an environmental co-benefit. With a population increasingly aware of current environmental issues, environmental considerations could be an additional motivating factor for patients when promoting a healthier diet or physical activity.

Sickle cell disease or drepanocytosis is caused by the polymerisation of abnormal haemoglobin S when oxygen tension decreases. This lead to the changes in the shape of red blood cells and anaemia. It has also been postulated that the red cells of patients with sickle cell disease contain a higher than normal concentration of calcium ions. These ions are bound to membrane proteins resulting in dehydration and loss of red blood cell deformability and cell-to-cell adherence. Anthocyanins extracted from some Congolese plants used in traditional medicine against sickle cell disease have recently been shown to have anti-sickling activity in vitro. Justicia secunda is a plant used in Congo by Jehovah's Witnesses, well known for their refusal of blood transfusions, against anaemia.Emmel, Itano and osmotic fragility tests were used to test the effect of anthocyanin extracts from Justicia secunda leaves on haemoglobin S solubility and sickle cell membrane stability.Anthocyanins from Justicia secunda were found to possess anti-sickling activity. Treated SS red blood cells recovered a normal, classical biconcave form with a radius of 3.3±0.3 μm, similar to that of normal erythrocytes. The solubility of deoxyhaemoglobin S increased and the osmotic fragility of drepanocytes decreased upon treatment with anthocyanin extracts.These findings suggest that anthocyanin extracts play a role in both stabilising the red blood cell membrane and inhibiting polymerisation of haemoglobin S. This provides a possible molecular basis for earlier reports on the anti-sickling properties of anthocyanins from some Congolese plants and their use in the management of sickle cell disease by Congolese traditional healers.

資料番号: SA0125672000