title: In vitro cell culture to study microglial inflammation

authors: Newland, Julia

subjects: CNs

abstract: Inflammation of the central nervous system (CNS) characterised by release of cytokines such as tumour necrosis factor-alpha (TNF-a) and interleukin-1 (IL-1) is an event that is often detrimental to neuronal cells and is thought to contribute to the neuronal loss observed during neurodegeneration.
One objective of this study was to investigate the potential anti-inflammatory properties of kawakawa leaf extracts using in vitro model cell systems. Kawakawa leaf extracts anti-inflammatory properties have anecdotally been documented in traditional Maori medicinal practices (Rangoa). However, before this aspect could be carried out, experiments were undertaken to investigate the effects the kawakawa leaf extracts had on the growth rates of two mammalian cell lines (HeLa and THP-1 cells).
Interestingly, the growth assays showed that the extracts to have both a stimulatory and inhibitory effect on cell growth. Toxicity of cells can be categorised as either necrotic or apoptotic cell death. In this study, HeLa cells and THP-1 cells were incubated under standard growth conditions with various concentrations (10 to 100ug/ml) of Kawakawa leave extracts prepared at room temperature or 60OC.
Growth data as seen in figures 2 and 3 typically have a long lag phase before they start to reach exponential growth between days 4 and 5. The extract having the largest stimulatory effect on HeLa cells as shown by figure 6 was 25 ug/ml at 60OC and the largest inhibitory effect seen on HeLa cells was seen at 50 ug/ml RT shown by figure 6. The extract which has the largest stimulatory effect on THP-1 cells is 25 ug/ml 60OC as shown by figure 11 whereas the extract producing the largest inhibitory effect is 25 ug/ml RT.

Apoptotic and necrotic cell death mechanisms were examined by using in vitro biochemistry techniques. Assessments were largely made based on biochemical changes of HeLa cells and THP-1 cells post treatment of Kawakawa leave extracts.
Measurement of lactate dehydrogenase (LDH assays) in the growth media of cells that were shown to be growth inhibited during exposure to Kawakawa extracts indicated that the growth inhibition resulting from exposure to the extracts was not due to necrotic cell death processes. (ie that cells maintained their membrane integrity) When compared to the control, a lower amount of cytosolic LDH was seen in THP-1 cell lines. However, HeLa cell lines produced a high level of cytosolic LDH which may be due to mycoplasma contamination. On average, Kawakawa concentrations at 12.5ug/ml and 25ug/ml yielded less lysed cells percentage across both cell lines.
The demonstrated cell growth inhibition was unlikely to be due to necrosis and because of this it was decided to see if cell death was caused by mitochondrial processes that would further support apoptotic cell death. The biochemical assay MTT indirectly measures mitochondrial dehydrogenase activity in the presence of kawakawa leave extracts.
The MTT data illustrated mitochondrial impairment where HeLa cells exposed to Kawakawa 60OC concentrations 6.25 ug/ml and 12.5 ug/ml had the lowest average mitochondrial activity. THP-1 cells exposed to Kawakawa 60OC concentrations 12.5 ug/ml and 50 ug/ml had the lowest average mitochondrial activity.
The main results of this study include, the treatment of HeLa and THP-1 cells with kawakawa extracts demonstrated that cytotoxicity was not due to necrosis. The most interesting finding of this study is when kawakawa extracts inhibit cell growth there is no increase in LDH. This is suggestive that the cellular membrane remains intact when exposed to the extract.

text: In vitro cell culture to study microglial inflammation Inflammation of the central nervous system (CNS) characterised by release of cytokines such as tumour necrosis factor-alpha (TNF-a) and interleukin-1 (IL-1) is an event that is often detrimental to neuronal cells and is thought to contribute to the neuronal loss observed during neurodegeneration.
One objective of this study was to investigate the potential anti-inflammatory properties of kawakawa leaf extracts using in vitro model cell systems. Kawakawa leaf extracts anti-inflammatory properties have anecdotally been documented in traditional Maori medicinal practices (Rangoa). However, before this aspect could be carried out, experiments were undertaken to investigate the effects the kawakawa leaf extracts had on the growth rates of two mammalian cell lines (HeLa and THP-1 cells).
Interestingly, the growth assays showed that the extracts to have both a stimulatory and inhibitory effect on cell growth. Toxicity of cells can be categorised as either necrotic or apoptotic cell death. In this study, HeLa cells and THP-1 cells were incubated under standard growth conditions with various concentrations (10 to 100ug/ml) of Kawakawa leave extracts prepared at room temperature or 60OC.
Growth data as seen in figures 2 and 3 typically have a long lag phase before they start to reach exponential growth between days 4 and 5. The extract having the largest stimulatory effect on HeLa cells as shown by figure 6 was 25 ug/ml at 60OC and the largest inhibitory effect seen on HeLa cells was seen at 50 ug/ml RT shown by figure 6. The extract which has the largest stimulatory effect on THP-1 cells is 25 ug/ml 60OC as shown by figure 11 whereas the extract producing the largest inhibitory effect is 25 ug/ml RT.

Apoptotic and necrotic cell death mechanisms were examined by using in vitro biochemistry techniques. Assessments were largely made based on biochemical changes of HeLa cells and THP-1 cells post treatment of Kawakawa leave extracts.
Measurement of lactate dehydrogenase (LDH assays) in the growth media of cells that were shown to be growth inhibited during exposure to Kawakawa extracts indicated that the growth inhibition resulting from exposure to the extracts was not due to necrotic cell death processes. (ie that cells maintained their membrane integrity) When compared to the control, a lower amount of cytosolic LDH was seen in THP-1 cell lines. However, HeLa cell lines produced a high level of cytosolic LDH which may be due to mycoplasma contamination. On average, Kawakawa concentrations at 12.5ug/ml and 25ug/ml yielded less lysed cells percentage across both cell lines.
The demonstrated cell growth inhibition was unlikely to be due to necrosis and because of this it was decided to see if cell death was caused by mitochondrial processes that would further support apoptotic cell death. The biochemical assay MTT indirectly measures mitochondrial dehydrogenase activity in the presence of kawakawa leave extracts.
The MTT data illustrated mitochondrial impairment where HeLa cells exposed to Kawakawa 60OC concentrations 6.25 ug/ml and 12.5 ug/ml had the lowest average mitochondrial activity. THP-1 cells exposed to Kawakawa 60OC concentrations 12.5 ug/ml and 50 ug/ml had the lowest average mitochondrial activity.
The main results of this study include, the treatment of HeLa and THP-1 cells with kawakawa extracts demonstrated that cytotoxicity was not due to necrosis. The most interesting finding of this study is when kawakawa extracts inhibit cell growth there is no increase in LDH. This is suggestive that the cellular membrane remains intact when exposed to the extract.

year: 2016

title: Riperata kahutia: a woman of mana

authors: Nikora, Shelley Aroha

subjects: Riperata Kahutia

abstract: Riperata Kahutia is widely remembered as a leader in the history of Tūranganuiā-
Kiwa, who fought to retain and repossess land during the difficult times of the
1860's. During this period of rapid social change and political upheavals resulting
in injustices, the exercise of rangatiratanga took many forms. Responses to
change covered a wide spectrum and there was no 'right' way of doing things,
simply leaders making decisions on the basis of what they and their people
thought at the time were best. Riperata utilised the law as a means of retaining
the land and the mana of her people. While her status as a rangatira was never in
doubt, innuendo surfaced suggesting she may have received more land entitlement
than she was qualified for.
The activities by Riperata may have been different from other leaders but the
purpose was the same: to preserve the people and the land. Her strategies for
doing so, based on her inherited mana and upbringing, her knowledge of local iwi
traditions, her acquisition of new skills introduced by Pākehā and her innovative
approaches to exercising her rangatiratanga, make her a worthwhile study.
This thesis will support the viewpoint that Riperata Kahutia acted on behalf of her
people and for the good of her people. It will be argued Riperata was a visionary
who embraced the changes imposed upon a society enduring the consequences of
colonisation. A major objective is to dispel suggestions she embellished her
rights.

text: Riperata kahutia: a woman of mana Riperata Kahutia is widely remembered as a leader in the history of Tūranganuiā-
Kiwa, who fought to retain and repossess land during the difficult times of the
1860's. During this period of rapid social change and political upheavals resulting
in injustices, the exercise of rangatiratanga took many forms. Responses to
change covered a wide spectrum and there was no 'right' way of doing things,
simply leaders making decisions on the basis of what they and their people
thought at the time were best. Riperata utilised the law as a means of retaining
the land and the mana of her people. While her status as a rangatira was never in
doubt, innuendo surfaced suggesting she may have received more land entitlement
than she was qualified for.
The activities by Riperata may have been different from other leaders but the
purpose was the same: to preserve the people and the land. Her strategies for
doing so, based on her inherited mana and upbringing, her knowledge of local iwi
traditions, her acquisition of new skills introduced by Pākehā and her innovative
approaches to exercising her rangatiratanga, make her a worthwhile study.
This thesis will support the viewpoint that Riperata Kahutia acted on behalf of her
people and for the good of her people. It will be argued Riperata was a visionary
who embraced the changes imposed upon a society enduring the consequences of
colonisation. A major objective is to dispel suggestions she embellished her
rights.

year: 2009

title: Embracing uncertainty: Informing decisions on flood risk and land use planning in a changing climate

authors: Hanna, Christina Jane

abstract: To increase resilience, decisionmakers must embrace uncertainty by shifting from static planning to adaptive strategies incorporate scenarios, national equitable multiple that future support consistent policy, access and ensure to and understanding of evolving flood risk information.

text: Embracing uncertainty: Informing decisions on flood risk and land use planning in a changing climate To increase resilience, decisionmakers must embrace uncertainty by shifting from static planning to adaptive strategies incorporate scenarios, national equitable multiple that future support consistent policy, access and ensure to and understanding of evolving flood risk information.

year: 2025